This case is before the Court on a petition for review and to set aside an Order of the National Labor Relations Board and on a cross-application by the Board seeking enforcement of its Order. The Board affirmed the findings and conclusions of the Administrative Law Judge and adopted his Order in its entirety,1 holding that the petitioner, Johns-Manville Products Corporation, violated Sections 8(a)(1), 8(a)(3), and 8(a)(5) of the National Labor Relations Act [the Act], as amended, 29 U.S.C. § 151 et seq.,2 by unilaterally hiring permanent replacements for employees who had been lawfully locked out. As a remedy, the Board ordered, in addition to cease and desist provisions,3 that the Company reinstate the one hundred and seven locked out bargaining unit employees with back pay and, upon request, to bargain with the Oil, Chemical and Atomic Workers International Union, AFL-CIO [the Union]. After carefully examining the record, this Court4 finds that the Board erred in its conclusions. Therefore, we set aside the Board’s Order and decline to enforce it.
THE FACTS
The petitioner is engaged at its New Orleans plant in the manufacture of “organic felt,” which is a crude form of paper used as a base for asphalt roofing products which the Company produces at its plants in Georgia, Louisiana and California. The procedure for making organic felt consists of a series of steps by which the two basic raw materials, waste wood chips and waste paper, are decomposed, blended with water, and then dried out to finally form paper sheets. Breaks in the paper, especially while still a damp “web”, can be caused by striking the water mixture (the “slurry”) or the finished sheet with one’s finger or an object, or by changing the proper revolutions per minute of the rollers in the various dryer sections. Damage can also be caused by improperly adjusting the valves controlling the blending of paper and wood slurry stock. The evidence shows that sabotage in all these forms can be carried out *1129surreptitiously, making it difficult if not impossible to observe the guilty individual or individuals.5 Further, the large size of the physical plant precluded constant surveillance of the operations.6
After this Company purchased the New Orleans plant in 1964, the Union was certified by the Board as the unit employees’ exclusive collective bargaining representative.7 Since that time, the Company and the Union have entered into four successive two-year contracts, the latest of which was due to expire on October 12,1973. Negotiations began in September 1973, following the Union’s service of its 60-day notice of termination of contract. The parties met several times for the purpose of negotiating a new collective bargaining contract, but the parties could not agree in several areas.8
Prior to and during the negotiation period, the Company experienced an unusual amount of production disruption which became more widespread and serious as negotiations progressed. An inordinate number of paper breaks occurred on or about August 21 or 22,1973 which were the result of improper adjustment of dryer section controls. On August 23, Darrell Wells, the Company’s Employee Relations Manager for the New Orleans plant, telephoned Ernest Rousselle, the Union’s International Representative, and informed him of this problem. Wells said this type of activity could “only hurt negotiations” and that the plant was not going to continue to operate and make scrap. Rousselle replied that he would check with Local Union officials and get back to him. However, Rousselle did not contact Wells on this subject and the next time it was discussed was at a bargaining meeting held about two months later on October 3, 1973.
From September 1 through October 22, 1973, according to the record, the number of paper breaks during production periods was fifteen to twenty per week in contrast to one to three per week during periods when negotiations were not in progress.9 Moreover, these breaks occurred on a daily basis and on all three shifts, with the excessive number of paper breaks generally coinciding with negotiation sessions.
Paper breaks were not the only problem. On the day before the October 3rd bargaining meeting, for example, the fine mesh stainless steel surface of a cylinder on one of the paper forming machines was “sharpr *1130ly cut” along its circumference. James Weil, the Company’s plant manager, testified that in thirty-five years experience he had never seen that kind of damage to a cylinder and that usually the type of damage resulting from wear and tear to such cylinders consists of dents or cuts, which are generally across the cylinder, rather than in the direction of its circumference. The repair of this cylinder cost approximately $4,000.
*1129I find the frequency rate of paper breaks during the nonnegotiating periods was about eight (8) per week, instead of three (3) per week as Respondent [the Company] contends, or considerably more per week as the employee witnesses contend. This figure makes allowance for inaccuracies and bias on the part of witnesses for both parties.
*1130On the same day it was discovered that a 2,300 volt electrical switch had been opened or disconnected causing a complete shutdown of the mill. This switch is located in the defibrator building, separate and apart from the building in which excessive paper breaks were occurring. The uncontradicted testimony is that this incident could not have happened accidentally because the switch is held in a closed position, not only by a mechanical catch, but also by a heavy rubber band. Weil saw the switch in the open position with the broken rubber band on the floor. Despite the absence of the rubber band, the mechanical catch would have been sufficient to hold the switch closed, if it too had not been released.
As a result of the above described production disruption and damage, James Weil approached the Union's president, Mack Jordan, and asked him to see whether anything could be done about individuals tampering with equipment and causing production delays. Jordan was angered by Weil’s request, did not respond to him, and took no affirmative action. At the negotiation meeting on the following day, October 3, 1973, Rousselle said he was “disturbed” because on the previous day Weil had accused Mack Jordan and other Union members of deliberately disrupting production.10 Wells responded by saying that the Company would not tolerate a continuation of disruptions in production and that they interfered with “the climate of the negotiations”. Wells then made an “official” request of the Committeemen that they see to it that production disruptions cease immediately. None of them made any reply to this request.
Immediately thereafter, a vibration developed in one of the three defibrators, requiring it to be shut down. Ball bearings were discovered between its rotating grinding discs.
Sometime about October 11, 1973, the Union held a strike vote among the bargaining unit employees and Rousselle thereafter applied to the International for strike authorization which it granted on October 23, 1973. Although a strike vote had been taken and a strike authorized, Rousselle admitted he never presented any Company offer to the rank and file for a vote.
At the October 12th negotiation meeting, the parties had reached a bargaining impasse.
By October 11th and 12th, paper breaks on both forming machines were so frequent that the machines became inoperable because the pits beneath them were filled with scrap paper. At this point the Company decided to cease operations and lay off 70-80 production employees for a few days. During this time a maintenance crew checked and repaired all the machinery, determining that the recent paper breaks and other problems were not the result of machinery or equipment malfunctioning. Weil testified:
I found as a result of the shut down . there was nothing found during that period of time that would have contributed to the vast number of breaks that we had on the machines.
The Company recalled production employees on October 22nd in the hope that operations would return to normal. However, sabotage of products and equipment reached a crescendo on that date. The record shows that all three defibrators were jammed with junk metal and had to be shut *1131down and that there was a multitude of paper breaks. The Government’s rebuttal witness Donald Hall agreed the situation was “unusual.” On his 3:00 p. m. to 11:00 p. m. shift there were as many as six breaks an hour on one machine. Paper breaks on the 22nd were so numerous that in the twenty-four hour period on that date, only thirteen and one-half tons of felt were produced, compared to normal daily production of one hundred and ten to one hundred and twenty tons.
Jim Weil, an expert with over thirty years experience in the paper industry, testified that if the scrap metal found in the bins and screw conveyor chamber had worked its way to the grinding surfaces of the discs, they would have caused an explosion which could have severely damaged the machine and endangered human lives.
Due to the continuing sabotage, it was decided between October 22 and October 31 that plant operations could not continue without serious risk to lives and property. On October 31, 1973, the Company held a meeting first with the Union Committee and then with all the production employees, informing them that it had been decided to discontinue operations with bargaining unit personnel until a contract was agreed upon. A letter to this effect was also sent by registered mail to the home of each employee. The Company’s spokesmen explained that the decision to lay off the employees had been made primarily to protect the employees’ safety and to preserve the Company’s assets. Additional reasons given for the lock-out were the Union’s unreasonable demands, unresponsive attitude and willful acts, as well as the history of sabotage during prior negotiations between the parties.11 When the Company representatives finished speaking, Union Representative Rousselle stated, “You let us go before and we will go again. . . .We can hold out to any amount of pressure you can give us. We will not settle for any less than the other plants.” A Union Committeeman added, “We don’t care if you shut the plant down for six months.”12
The plant was indeed shut down and the production employees laid off. On November 14, 1973, the Company resumed partial operations using temporary replacements and employees loaned by the Company’s other plants.
The' parties continued to meet for the purpose of negotiating a new contract. On November 14, 1973, the same day the Company resumed partial production with temporary replacements, the Company presented an improved proposal to the Union. The Union rejected the Company’s proposal and offered a counterproposal, which the Company rejected. Subsequent meetings were held on November 27 and November 30, 1973, and on January 23 and March 20, 1974, but the impasse continued.
Reports to the Company concerning the output and profitability of the New Orleans operation during the time when temporary replacements were being used indicated that the Company was losing approximately $300,000 per month in pre-tax profits. Further, due to vastly reduced output, the Company had been forced to curtail opera*1132tions at two other plants which relied on New Orleans for paper. The record reveals that the Company representatives involved in negotiations or responsible for the New Orleans operation met together after the March 20th negotiations to consider the alternatives. According to the testimony, there were four reasons for their conclusion that the only course left was to hire permanent replacements: (1) with contract negotiations stalemated, it did not seem reasonable to resume operations with bargaining unit employees without a contract, based on the history of sabotage and disruption preceding the lay-off on October 31, 1973; (2) the use of salaried employees and temporary hourly replacements was not producing the required volume and the costs were excessive; (3) the Company was suffering an economic loss of between $280,000 and $300,000 per month, which from November 1, 1973 through March 31, 1974, amounted to a total of about $1.5 million; and (4) the adverse effect the New Orleans labor dispute was having on other plants within the residential products division, including a decrease in the number of employees and days of operations.
After the Company decided it was necessary to hire permanent replacements, it started interviewing applicants. Although seven new people started working the second week of April, 1974, the full one hundred seven employees were not replaced until late June or early July. On June 12, 1974, before the workforce was completely replaced, the parties met and bargained, but without success.
FINDINGS
The role of this Court in reviewing the order of the National Labor Relations Board is to determine whether the Board’s decision is supported by substantial evidence on the record as a whole,13 or is a proper application of the law.14 This Court has the utmost respect for findings and conclusions of the Board, but recognizes that their judgment is not “the last word.” As the Supreme Court stated in N.L.R.B. v. Brown, 380 U.S. 278, 85 S.Ct. 980, 13 L.Ed.2d 839 (1965):
It is argued, finally, that the Board’s decision is within the area of its expert judgment and that, in setting it aside, the Court of Appeals exceeded the authorized scope of judicial review. This proposition rests upon our statement in Buffalo Linen [Labor Board v. Truck Drivers Union, 353 U.S. 87, 77 S.Ct. 643, 1 L.Ed.2d 676 (1957)] that in reconciling the conflicting interests of labor and management the Board’s determination is to be subjected to “limited judicial review.” 353 U.S., at 96 [77 S.Ct. 643]. When we used the phrase “limited judicial review” we did not mean that the balance struck by the Board is immune from judicial examination and reversal in proper cases. Courts are expressly empowered to enforce, modify or set aside, in whole or in part, the Board’s orders, except that the findings of the Board with respect to questions of fact, if supported by substantial evidence on the record considered as a whole, shall be conclusive. National Labor Relations Act, as amended, §§ 10(e), (f), 29 U.S.C. §§ 160(e), (f) . . Courts should be “slow to overturn an administrative decision,” Labor Board v. Babcock & Wilcox Co., 351 U.S. 105, 112 [76 S.Ct. 679,100 L.Ed. 975], but they are not left “to ‘sheer acceptance’ of the Board’s conclusions,” Republic Aviation Corp. v. Labor Board, 324 U.S. 793, 803 [65 S.Ct. 982, 89 L.Ed. 1372]. Reviewing courts are not obliged to stand aside and rubber-stamp their affirmance of administrative decisions that they deem inconsistent with a statutory mandate or that frustrate the congressional policy underlying a statute. Such review is always properly within the judicial province, and courts would abdicate their responsibility *1133if they did not fully review such administrative decisions. Of course due deference is to be rendered to agency determinations of fact, so long as there is substantial evidence to be found in the record as a whole. But where, as here, the review is not of a question of fact, but of a judgment as to the proper balance to be struck between conflicting interests, “[t]he deference owed to an expert tribunal cannot be allowed to slip into a judicial inertia which results in the unauthorized assumption by an agency of major policy decisions properly made by Congress.” American Ship Building Co. v. Labor Board, [380 U.S. 300, 318, 85 S.Ct. 955, 957, 13 L.Ed.2d 855 (1965)] [footnote citation omitted]. 380 U.S. 278, 290-92, 85 S.Ct. 980, 987, 13 L.Ed.2d 839.
In the instant case the Board, in accordance with the finding of the Administrative Law Judge, held that “the evidence in this record is insufficient to support a conclusion and finding that [the Company’s] employees engaged in an in-plant strike or in concerted improper conduct so as to enable it to replace or discharge its entire complement of production employees.” We agree with the factual findings of the Administrative Law Judge and the Board, but not with the conclusions they reached.
Based on the facts as discussed above, this Court finds that, as a matter of law, the employees were involved in what amounted to an in-plant strike. The employees’ conduct was so severe that we cannot help but find that their behavior was tantamount to a strike and forced the Company to lock them out. The Company’s reaction had a valid, substantial business justification and there was no anti-union motivation indicated by the record or found by the Board or asserted by the Union. The history of the relationship between the parties reveals the Company’s continuing desire to negotiate and full recognition and acceptance of the Union, notwithstanding numerous incidents of prior sabotage by the employees. In the most recent negotiation period, Company management on at least two occasions requested Union officials to see if something could be done about individuals causing damage and disruptions; the Union never responded, or expressly denied the allegations. In the interest of public policy and industrial peace, we cannot condone behavior which causes actual and substantial damage to property or potential, serious injury to human lives. Although employees and employers are permitted to choose their own weapons in the bargaining battle,15 the employees in the instant case went too far. Since we find their actions amounted to a strike, the Company’s subsequent lock-out and hiring of permanent replacements were not violative of the National Labor Relations Act, including Sections 8(a)(1), (3) and (5). National Labor Relations Board v. Mackay Radio & Telegraph Co., 304 U.S. 333, 58 S.Ct. 904, 82 L.Ed. 1381 (1938).16 This conclusion pre*1134eludes the necessity of considering the other issues raised by the parties,17 particularly the question of whether an employer may permanently replace locked out employees after bargaining impasse.18
*1135Johns-Manville’s petition to set aside the order of the National Labor Relations Board is hereby granted and the Board’s cross-petition for enforcement of said order is hereby denied.
. The Board’s Decision and Order are reported at 223 NLRB No. 189 (1976).
. The pertinent statutory provisions are as follows:
29 U.S.C. § 158 [§ 8, National Labor Relations Act]
(a) It shall be an unfair labor practice for an employer—
(1) to interfere with, restrain, or coerce employees in the exercise of the rights guaranteed in section 157 of this title . .
(3) by discrimination in regard to hire or tenure of employment or any term or condition of employment to encourage or discourage membership in any labor organization . . .
(5) to refuse to bargain collectively with the representatives of his employees, subject to the provisions of section 159(a) of this title . . ..
. “The Johns-Manville Products Corporation, Respondent herein, its officers, agents, successors and assigns, shall:
1. Cease and desist from:
(a) Discharging or otherwise discriminating against employees in regard to hire or tenure of employment, or any term or condition of employment because of protected concerted activities.
(b) In any other manner interfering with, restraining or coercing employees in the exercise of their rights guaranteed in Section 7 of the Act except to the extent that such rights may be effected by lawful agreements in accord with Section 8(a)(3) of the Act.”
. This Court has jurisdiction under Section 10(e) and (f) of the National Labor Relations Act, 29 U.S.C. § 160(e) and (f).
. Government witness St. Angelo testified that the sheets, particularly at the point just in front of the dryer section, can easily be broken and that this can be done without others in the vicinity observing it.
. The operations are housed in five separate buildings having a total of approximately forty thousand square feet of floor space and are conducted by three shifts of employees per day.
. A substantial number of these employees had worked for the former owner of the plant, Flintkote Company, and had been represented by the Union since 1947.
. Apparently the most controversial proposal by the Company would have permitted it to hire mechanics from outside the bargaining unit, relieving it of the obligation to train maintenance department employees to do mechanics’ work. The Company urged this proposal, contending that the lack of sufficiently trained maintenance people was affecting its maximum productivity. The Union opposed this change because it believed that senior maintenance employees would be laid off in favor of less senior, but more skilled mechanics hired from the outside. The parties also disagreed on the duration of a new contract and a wage increase, the Company suggesting a three year contract and conceding to a 17, 20, and 25 cent wage increase per year, and the Union asking for a one year contract with a 30 cent wage increase each year. Further, in addition to other proposals from each side, the Company wanted to delete a no-strike, no slowdown, no work stoppage, and no lockout clause, and the Union wanted increased fringe benefits.
. Based on the conflicting testimony presented at the hearing, the Administrative Law Judge found that the more accurate number of paper breaks during non-negotiating periods would be about eight per week:
. At the meeting, Rousselle also explained that several months earlier he showed the Company a large piece of metal which was found in the raw materials, and that Mr. Weil had stated at that time that the Company was purchasing the paper chips from any place they could get them and that the Company was not accusing the employees of causing the breakdowns which resulted from the foreign materials.
. Testimony at the hearing before the Administrative Law Judge shows that similar incidents of sabotage had occurred in earlier negotiations. During ten weeks of the negotiations resulting in the 1965 contract, there was an average of 9.3 paper breaks per week. In the 1969 negotiations there was a forced shutdown from October 11 through October 27 because fifteen to twenty paper breaks during the week of October 6 had caused the pits to fill up. During the 1971-72 negotiations, paper breaks averaged fifteen to twenty per week from January, 1972 until May or June, 1972 when the contract was settled.
. The six month time period refers to the maximum period the employees might be eligible for unemployment compensation benefits, assuming it was determined that the employees were not involved in a labor dispute. From the end of October through the month of April, eighty-eight of the one hundred seven members of the bargaining unit applied for and were awarded such benefits, see Johns-Manville Products Corp. v. Doyal et al., 510 F.2d 1196 (5th Cir. 1975). Employees received 54% of their average gross weekly pay. In addition to unemployment benefits the Union also provided the employees with weekly benefits, characterized by Rousselle as “lock-out benefits.”
. NLRB v. Brown, 380 U.S. 278, 291, 85 S.Ct. 980, 983, 13 L.Ed.2d 839, 849 (1965); Universal Camera Corp. v. NLRB, 340 U.S. 474, 71 S.Ct. 456, 95 L.Ed. 456 (1951).
. Labor Board v. Wilcox Co., 351 U.S. 105, 112-13, 76 S.Ct. 679, 100 L.Ed. 975 (1956); NLRB v. Insurance Agents Intern’l Union, 361 U.S. 477, 80 S.Ct. 419, 4 L.Ed.2d 454 (1960).
. Quoting from NLRB v. Insurance Agents, 361 U.S. 477, 80 S.Ct. 419, 4 L.Ed.2d 454 (1960), the Supreme Court has stated:
Our decisions hold that Congress meant that these activities [attempting to exert economic strength], whether of employer or employees, were not to be regulable by States any more than by the NLRB, for neither States nor the Board are “afforded flexibility in picking and choosing which economic devices of labor and management would be branded as unlawful.” . . Rather, both are without authority to attempt to “introduce some standard of properly ‘balanced’ bargaining power,” . or to define “what economic sanctions might be permitted negotiating parties in an ‘ideal’ or ‘balanced’ state of collective bargaining.” Lodge 76, Etc. v. Wisconsin Employment Relations Comm’n, 427 U.S. 132, 96 S.Ct. 2548, 2557, 49 L.Ed.2d 396 (1976).
See also, Inter-Collegiate Press v. NLRB, 486 F.2d 837, 847 (8th Cir. 1973) (“Neither the Board nor the courts should sit as arbiters of the permissible economic weapons available to the parties in a labor dispute”); NLRB v. Dalton Brick & Tile Corp., 301 F.2d 886, 895 (5th Cir. 1962).
. In Mackay Radio, the Supreme Court held that it was not an unfair labor practice for the employer to replace his striking employees with other employees in an effort to carry on his usual business and neither was the employer bound to later discharge the more-recently-hired employees in order to reinstate the strikers. However, the employer was found to have committed an unfair labor practice in violation of § 8 of the National Labor Relations Act *1134when he discriminated against certain of the strikers by refusing to rehire them for the sole reason that they had been active in the union.
. The Administrative Law Judge and the Board in the instant case determined that the employees were not engaged in an in-plant strike or concerted action sufficient to justify the Company’s permanently replacing them without notice after a lawful lockout and bargaining impasse; that such action tilted the scales out of balance with respect to bargaining power; and that such action also rendered more than a slight adverse effect upon the employees’ protected rights, as compared with the Company’s legitimate business purpose and its lockout bargaining leverage. The Administrative Law Judge further found, and the Board agreed, that the Company’s action was so inherently discriminatory and destructive of the employees’ rights that such action constituted a per se violation of Section 8(a)(1) and (3) of the Act. It was further held that the hiring of permanent replacements in effect constituted a withdrawal of recognition of the employees’ elected bargaining representative and was indicative of bad faith bargaining or refusing to bargain on the part of the Company, all in violation of Section 8(a)(5) of the Act.
In passing we would like to note that when certain conduct by an employer is found to be “inherently destructive” of employees’ rights, the conduct is deemed to be a per se violation and it is unnecessary to examine the employer’s intent behind that conduct in order for the employer to be guilty of having violated the Act. When the employer’s conduct is not inherently destructive but rather has only a comparatively slight impact or slight adverse effect on employees’ rights, then intent becomes an important issue. If there is subjective evidence of anti-union motivation, then the employer has committed a violation. In the absence of anti-union motivation, a balancing test is done to determine whether the employer’s legitimate business reasons outweigh the effect on the employees’ protected statutory rights. NLRB v. Fleetwood Trailer Co., 389 U.S. 375, 380, 88 S.Ct. 543, 19 L.Ed.2d 614 (1967); NLRB v. Great Dane Trailers, Inc., 388 U.S. 26, 34, 87 S.Ct. 1792, 18 L.Ed.2d 1027 (1967); NLRB v. Brown, 380 U.S. 278, 287, 85 S.Ct. 980, 13 L.Ed.2d 839 (1965). Because the Board and the Administrative Law Judge held the conduct of the employer in the present case to be a per se violation, there was no need to go any further. But as long as they attempted to perform the balancing test, we observe the instruction of judicial precedent that neither the Board nor the courts are permitted to choose the weapons or balance the bargaining power of the parties beyond that delineated by Congress in the National Labor Relations Act and other federal and state labor law. See n. 15 infra. As noted in the text, however, due to our disposition of the case before us, we need not reach these issues.
. In American Ship Bldg. v. Labor Board, 380 U.S. 300, 85 S.Ct. 955, 13 L.Ed.2d 855 (1965), the Supreme Court held that an employer does not commit an unfair labor practice under the Act when, after an impasse in negotiations has been reached, he temporarily shuts down his plant and lays off his employees for the sole purpose of applying economic pressure in support of his bargaining position. However, in a footnote, the Court expressly reserved ruling as to the consequences that would follow if an employer replaced his employees with permanent replacements or temporary help. Id. at n. 8.
This Court in National Labor Relations Board v. Dalton Brick and Tile Corp., 301 F.2d 886 (5th Cir. 1962), upheld the use of a lockout for legitimate bargaining purposes when not accompanied by any anti-union animus.
The Eighth Circuit went one step further by holding that an employer’s conduct in hiring temporary replacements during a lawful lockout was not “inherently destructive” of employees’ rights and, balanced on the facts presented in that case, was not a violation of the Act. Inter-Collegiate Press v. NLRB, 486 F.2d 837 (8th Cir. 1973), cert. denied, Bookbinders Local No. 60 v. NLRB, 416 U.S. 938, 94 S.Ct. 1939, 40 L.Ed.2d 288. This approach was adopted by the Administrative Law Judge in the instant case in reference to the hiring of temporary employees after the lockout, with no party challenging it.
One year ago in Lodge 76, Intern’l Assoc. of Machinists and Aerospace Workers, AFL-CIO v. Wisconsin Employment Relations Comm’n, 427 U.S. 132, 96 S.Ct. 2548, 49 L.Ed.2d 396 (1976), the Supreme Court considered federal preemption of state regulation of a group of employees’ concerted refusal to work overtime while a new contract was being negotiated. After holding that the state was preempted from regulating such conduct (although such conduct was not expressly protected or prohibited by the Act), the Supreme Court stated:
Moreover, even were the activity presented in the instant case “protected” activity within the meaning of § 7, economic weapons were available to counter the union’s refusal to work overtime, e. g., a lockout, American Ship Building Co. v. NLRB, 380 U.S. 300, 85 S.Ct. 955, 13 L.Ed.2d 855, and the hiring of permanent replacements under NLRB v. Mackay Radio & Tel. Co., 304 U.S. 333, 58 S.Ct. 904, 82 L.Ed. 1381 (1938). [footnote omitted], 96 S.Ct. at 2559.
*1135Although we adhere carefully to the words of the Supreme Court we would not say at this time that the above statement clearly indicates whether the hiring of permanent replacements in the absence of a strike (as in Mackay, supra, n. 16) would be a violation of the Act.