In the wake of Monday’s presidential debate, Donald Trump and his supporters have devoted much of the week to defending the Republican position on the appropriate amount of weight a woman may gain after being crowned Miss Universe. Americans who take an interest in the subject of trade, however, have been debating another one of the claims Trump made that night. While vigorously assailing NAFTA, he attacked Hillary Clinton’s record on trade, and her husband’s; the treaty “is the worst trade deal maybe ever signed anywhere,” in his telling, and as he said to Clinton: “your husband signed” it.

The treaty in question is one I feel strongly about, for the reasons I laid out in the October issue. No trade deal is perfect, and the best of them are bound to have disruptive effects on the economies. That is, in a sense, what they are designed to do. More to the point, the disruptive effects may be adverse for specific industries and regions. and I think we can all agree that it’s important for policymakers to keep that in mind as they negotiate such agreements. States like Indiana and cities like Pittsburgh are proof that it’s possible to be resilient in the face of change and even to emerge revitalized, but that isn’t guaranteed and doesn’t happen by magic. With that said, it’s been more than twenty years since the passage of NAFTA, and the evidence shows that it has helped foster economic growth in the United States, Mexico, and Canada. Trump is flatly wrong to blame Bill Clinton for his role in its passage, because he is flatly wrong to blame anyone for their efforts on behalf of a treaty that has proven to be one of America’s better deals.

Trump is, however, correct to say that Bill Clinton signed NAFTA. He would also have been correct if he had said that Clinton’s predecessor, George H.W. Bush, signed it and he would have been correct if he had said that they both did. There is documentary evidence that both men did so. Here is a video of Bush signing NAFTA, on December 17th, 1992. Here is a video of Clinton signing NAFTA, on December 8th, 1993. Here is a technical explanation, from the Baltimore Sun, of the reason that Bush’s signature, in 1992, was not sufficient to implement the treaty:

Mr. Bush had to allow Congress 90 days to consider the agreement before signing. Yesterday was the first possible day for his signature. The clock will start ticking again when Mr. Clinton submits implementing legislation to make the necessary changes in U.S. law and tariffs required by the treaty. There is no deadline for Mr. Clinton to take this action, but once he does Congress will have up to 90 legislative days to vote up or down on the implementing legislation or change it.

In other words, despite our contemporary disregard for Congress, the legislative branch exists, and the founding fathers of our nation accorded it certain powers. NAFTA is a congressional-executive agreement; as the Cato Institute’s Scott Lincicome explained recently, that means that after being signed by the president, it had to be converted into implementing legislation, by Congress, prior to being passed into law. Bush was the president when NAFTA was being negotiated, but his signature on the treaty was not sufficient to pass it into law, and about a month later, Clinton had become president. Worth noting, though, is that Clinton’s signature was not merely a formality. NAFTA was controversial at the time, with Democrats leading the opposition to it. This opposition persisted even after Bush signed the treaty, and after Clinton was inaugurated as his successor; ultimately, the Senate ratified the treaty only after Clinton negotiated side agreements, addressing concerns about labor and the environment.

In other words, Bush spearheaded the effort to pass NAFTA. And although Republicans led the charge in Congress, it would be remiss for a Texan to ignore the crucial support they received from Texas Democrats such as Lloyd Bentsen, then our senior senator—or to miss the opportunity to commend Texas Democrats in Congress today, such as Joaquin Castro, Eddie Bernice Johnson, and Henry Cuellar, whose support for the Trans-Pacific Partnership has put them at risk of some backlash from the left. And the Clinton administration did real work to complete what Bush started. There’s been a lot of reminiscing, this week, about Al Gore’s substandard debate performances during the 2000 presidential election, but very few reminders about how compellingly he made his case when he debated Ross Perot on the subject of NAFTA, shortly before the ratification vote, in November 1993.

It can be a little tricky to characterize the respective roles that Bush and Clinton played in the NAFTA process. But to say that only one of them was relevant would be flatly ahistorical, and to say that either party is solely culpable would be disingenuous. The truth is that both parties deserve credit for NAFTA, as do both of the presidents who signed it—for the treaty itself, and for their willingness to put aside partisanship to achieve its passage.