IMO some sort of union-curbing legislation was almost inevitable in 1947; the public (including some union members!) was angered by the postwar strike wave--this was one major reason for the Republican victory in 1946. (The GOP slogan "Fed up?" referred largely to the strike wave.) The Case bill, a milder forerunner of Taft-Hartley, easily passed the Democratic 79th Congress, which came close to overriding Truman's veto. As for Taft-Hartley, one should note that Hartley's bill that passed the House was harsher toward labor than the final bill; Senator Taft in the Senate watered it down somewhat to assure that a moderate Republican like Irving Ives of New York would vote to override Truman's anticipated veto. If that wasn't quite enough, Taft would have watered it down a bit more--but some sort of bill would have passed.
On the actual effects of Taft-Hartley: One thing that is often neglected is that even without section 14(b) (which authorized states to outlaw the union shop within their jurisdictions) it is arguable that states could pass "right-to-work" laws. To quote an old post of mine:
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Is it actually clear that without 14(b) states would not be able to pass "right to work" laws? Arkansas and Florida actually enacted such provisions in their state constitutions during World War II. See Chapter Two, "Putting the Shackles on Labor: The AFL and the Fight Against the Open Shop" in Andrew E. Kirsten, *Labor's Home Front: The American Federation of Labor During World War II* (New York University Press 2006). The validity of Florida's provision was sustained by a federal district court in florida in in *American Federation of Labor v. Watson,* 60 F.Supp. 1010 (S.D. Fla. 1945).
http://www.leagle.com/decision/1945107060FSupp1010_1845/AMERICAN FEDERATION OF LABOR v. WATSON The AFL had argued that the provision was invalid for a number of reasons, some having to do with the US Constitution and others related to the provision's alleged conflict with the Wagner Act (which, the AFL maintained, gave unions and employers the right to bargain for a closed shop). The court's decision stated that
"In view of the fact that no labor legislation by Congress has required an employee to belong to a labor union or has made the closed shop mandatory, but on the contrary the Federal public policy in regard to compulsory membership in labor unions is stated in Section 102 of Title 29, U.S.C.A., as follows:
"* * * the individual unorganized worker is commonly helpless to exercise actual liberty of contract and to protect his freedom of labor, and thereby to obtain acceptable terms and conditions of employment, wherefore, though he should be free to decline to associate with his fellows, it is necessary that he have full freedom of association, self-organization, and designation of representatives of his own choosing, to negotiate the terms and conditions of his employment, * * *." (Emphasis supplied.)
and in view of the provisions of the Florida amendment that it shall not be construed to deny or abridge the right of employees by and through a labor union to bargain collectively with an employer, there does not appear to be any provision of the Federal labor regulatory statutes with which the constitutional amendment collides.."
The AFL appealed to the US Supreme Court, which issued its opinion in *American Federation of Labor v. Watson* on March 25, 1946 in
http://caselaw.findlaw.com/us-supreme-court/327/582.html Justice Douglas's opinion seemed sympathetic in tone to the unions--Douglas refers to "The loss in bargaining position by the unions, the disruption of harmonious relationships between the union and the employers, the almost certain decrease in union membership..." which the Florida constitutional provision might cause--but in fact in the end it does not decide the issue whether the provision violated the Wagner Act. It decided instead that the District Court should not have passed on the merits before the Florida state courts got a chance to interpret the provision in question:
"There is, in the first place, some question whether this new provision of Florida's constitution is self-executing11 or requires legislation for its enforcement. 12 The District Court itself took the view that it is not self-executing and noted that no enforcing legislation has been enacted. If, on the other hand, it be assumed, as Florida's Attorney General asserts, that this constitutional provision is self-executing, we do not know what sanctions Florida will afford for its enforcement. It provides that 'The right of persons to work shall not be denied or abridged on account of membership or non-membership in any labor union, or labor organization.' It is asserted that this provision outlaws the closed- shop agreement and makes those who enter into one criminally liable,13 or, in case of corporations, subjects them to quo warranto proceedings... So far as we know, however, it may not have that effect but do no more than give to an individual working man a cause of action in case the rights granted him are denied or abridged. Or as in the case of contracts in restraint of trade at common law, it may make closed-shop agreements unlawful only in the sense that courts will not enforce them. 15 The proviso itself raises questions of interpretation which when authoritatively settled may put the constitutional issues now sought to be raised in quite a different light or even eliminate some of them. The proviso states that 'this clause shall not be construed to deny or abridge the right of employees by and through a labor organization or labor union to bargain collectively with their employer.' The bill alleges that the right to bargain collectively granted by the National Labor Relations Act includes the right to a closed-shop agreement 16 Conceivably the proviso may be construed to make this Florida law applicable only to enterprises not subject to the National Labor Relations Act. Or the right to bargain collectively, recognized by the proviso, may be construed to mean the right which is granted by the National Labor Relations Act..."
In other words, the Court dodged the question. The issue of the compatability of state right-to-work laws with the Wagner Act never came back to them, because the Wagner Act was soon amended (some would say replaced) by Taft-Hartley.
So if 14(b) had not been enacted, would this mean the Supreme Court would have declared state right-to-work laws contrary to the Wagner Act? It seems plausible that it would have, but we do not *know*.
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To this I would add that even if the Supreme Court in 1947 were to hold right-to-work laws contrary to the Wagner Act, a later, more anti-union Supreme Court could always overrule the decision. (This is significant because it would be decades before such laws would be enacted in major northern industrial states, and by that time we would have a very different Court from that of 1947. For a long time such laws were pretty much confined to Southern and rural Great Plains and Mountain states. )