What did the Taft-Hartley Act actually do?

It amended the National Labor Relations Act to ban secondary boycotts and other union conduct listed in 29 U.S.C. Section 158(b), let states outlaw union-shop contracts under Section 14(b), created a presidential injunction process for strikes that threaten national health or safety, and required union officers to file anti-Communist affidavits, a provision the Supreme Court upheld in American Communications Association v. Douds in 1950.

Is right-to-work a state law or a federal law?

Both, and the relationship is the point. The prohibition on union-shop agreements is written into state statutes, but Section 14(b) of the federal Taft-Hartley Act is what permits a state to enact one at all, by carving an exception into a national law that would otherwise pre-empt it.

Did Truman veto the Taft-Hartley Act?

Yes. Truman vetoed H.R. 3020 on June 20, 1947, calling it a bill that would 'reverse the basic direction of our national labor policy.' Congress overrode the veto within three days, and the bill became law without his signature.

How many right-to-work states are there right now?

Twenty-six, as of August 29, 2026. The count moves rarely: Michigan is the only state in decades to repeal an existing right-to-work law, doing so effective February 13, 2024, after 12 years with one in place.

What is a secondary boycott under labor law?

It is pressure aimed at a business the union has no direct dispute with, in order to reach the employer it does have a dispute with, for example picketing a retailer to stop it from carrying goods made by a struck manufacturer. Section 158(b)(4) makes most of this conduct an unfair labor practice for a union to engage in or induce.

What the Taft-Hartley Act actually took away

Right-to-work sounds like a state’s own idea, something a legislature in Little Rock or Topeka thought up on its own. It is a federal permission slip, one clause inside a 1947 law that a Republican Congress passed over Harry Truman’s veto, and without that clause no state right-to-work statute would survive contact with federal labor law for a single day.

The clause is Section 14(b) of the Labor Management Relations Act of 1947, better known by the names of its Senate and House sponsors, Robert Taft and Fred Hartley, and better known still by the shorthand that stuck: Taft-Hartley. It runs one sentence, now codified at 29 U.S.C. Section 164(b):

Nothing in this subchapter shall be construed as authorizing the execution or application of agreements requiring membership in a labor organization as a condition of employment in any State or Territory in which such execution or application is prohibited by State or Territorial law.

Read closely, it does not ban the union shop anywhere. It does something narrower and, for the labor movement, more damaging: it tells the states they are free to ban it themselves, opting out of a federal labor policy that had assumed, since the Wagner Act of 1935, that a union and an employer could agree to require membership as a condition of the job. Twenty-six states have since taken that opt-out, as of August 29, 2026. The number matters less than the direction of authority: state legislatures did not invent a workaround around federal law. Congress built the workaround into the federal law on purpose, in 1947, and states have been walking through the door it left open ever since.

What the bill actually changed

Taft-Hartley amended the National Labor Relations Act rather than replacing it, and most of what it changed ran the other direction from 14(b), restricting what unions could do rather than what employers could. The centerpiece is Section 8(b)(4), now 29 U.S.C. Section 158(b)(4), which made it an unfair labor practice for a union to induce a strike or to “threaten, coerce, or restrain” a neutral business, where the purpose was any of four things: forcing an employer to join an organization, forcing a business to stop dealing with another employer, forcing recognition of a union that had lost a certification election, or forcing an employer to assign work to one trade over another. That is the secondary boycott ban. Before 1947, a union fighting one employer could lawfully pressure that employer’s suppliers, customers, and haulers into cutting ties, and the pressure was often what made a strike work. After 1947, a union could still strike the employer it had a dispute with. It could no longer lawfully reach past that employer to squeeze the businesses around it.

The Act also gave the executive branch a tool it had never had in peacetime labor law: the national emergency injunction. Under what is now 29 U.S.C. Section 176, a president who judges that a strike or lockout would “imperil the national health or safety” can appoint a board of inquiry and ask a federal court for an injunction suspending the action for up to 80 days while the board reports and the National Labor Relations Board runs a secret ballot on the employer’s last offer. The clock inside that 80 days is specific: if there is no agreement 60 days in, the board reports the parties’ positions to the president, the NLRB runs its ballot in the following 15 days, and within 5 days of that vote the Attorney General moves to dissolve the injunction, offer accepted or not. It has been invoked against dockworkers and steelworkers in the decades since. It exists because Taft-Hartley put it there.

The same bill required union officers to sign affidavits swearing they were not members of the Communist Party before their union could use NLRB election machinery. The Supreme Court upheld that provision in 1950, in American Communications Association v. Douds, 339 U.S. 382, holding that Congress could reach it through the commerce power rather than treating it as a punishment for belief; Justice Jackson dissented in part. It is a reminder that Taft-Hartley was not one policy but a bundle of them, passed in the same 1947 session and overridden by the same two votes, and 14(b) is the piece of that bundle still doing the most work today.

The veto Congress erased in three days

Truman did not sign the bill and grouse about it later. He vetoed it on June 20, 1947, and sent Congress a message that did not hedge:

The bill taken as a whole would reverse the basic direction of our national labor policy, inject the Government into private economic affairs on an unprecedented scale, and conflict with important principles of our democratic society.

On the secondary boycott ban specifically, he argued it would strip workers of a tool against exactly the kind of employer it was meant to protect:

It would deprive workers of the power to meet the competition of goods produced under sweatshop conditions by permitting employers to halt every type of secondary boycott, not merely those for unjustifiable purposes.

And on the union shop, he made the argument that Section 14(b) later proved right in practice, that a law claiming to preserve something while burying it in procedure is not preserving it:

While seeming to preserve the right to agree to the union shop, it would place such a multitude of obstacles in the way of such agreement that union security and responsibility would be largely cancelled.

Congress was not moved. The House overrode the veto the same day, June 20, 1947, by a vote of 331 to 83. The Senate followed on June 23 by 68 to 25, and the Labor Management Relations Act became law without a presidential signature, three days after Truman put his objections in writing. A veto message that reads, eight decades later, like an accurate forecast did not slow the bill down at all.

Twenty-six states, one federal clause

Every right-to-work statute on the books, from Texas’s 1947 law to South Dakota’s constitutional provision, exists inside the space Section 14(b) opened. As of August 29, 2026, that is 26 states: Alabama, Arizona, Arkansas, Florida, Georgia, Idaho, Indiana, Iowa, Kansas, Kentucky, Louisiana, Mississippi, Nebraska, Nevada, North Carolina, North Dakota, Oklahoma, South Carolina, South Dakota, Tennessee, Texas, Utah, Virginia, West Virginia, Wisconsin, and Wyoming, according to the National Conference of State Legislatures. The count has moved only once against the trend in decades: Michigan adopted a right-to-work law in 2012, then repealed it, with the repeal taking effect February 13, 2024, after twelve years on the books. No other state has reversed one.

The mechanism is worth sitting with, because it inverts how the two levels of government usually work in labor law. Federal law ordinarily pre-empts conflicting state law; a state cannot pass its own version of the NLRA and expect it to govern instead. Section 14(b) is Congress deliberately declining to pre-empt, carving a specific, named exception into its own statute so that a state law banning union-security agreements survives instead of being struck down as inconsistent with federal policy. A state legislature that bans the union shop is not asserting authority Congress overlooked. It is using authority Congress handed it in the same 1947 bill that banned secondary boycotts and created the emergency injunction, three provisions that read, in the text Congress passed, as one coherent project: shrink what unions can do collectively, and let states shrink what they can require individually.

What this means for how organizing works now

A union organizing a shop in Nebraska or Texas today has to persuade workers both that a union is worth having and that they should pay for one voluntarily, in a workplace where a majority can vote a union in as the exclusive bargaining representative and still not be able to require the dues that fund the representation they voted for. That gap, a certified union with no guaranteed dues base, is the practical daily effect of 14(b), and it is why the National Right to Work Committee and its allies have spent decades trying to extend the same clause nationally through a federal right-to-work bill that has never passed. Taft-Hartley did not eliminate the union shop. It handed each state a switch to turn it off, and a bit over half the states have thrown that switch, one statehouse at a time, on the authority of a sentence written into federal law in 1947 and never repealed.