A north America trade pact was kicking around for years. It took the fall of Soviet and East European communism to get NAFTA rolling and passed under Clinton. Prime culprits are George Bush, Bill Clinton, Robert Rubin who was Secretary of the Treasury and the Republicans in the Senate and House who voted for NAFTA in greater numbers than did the Democrats.
Ronald Reagan had just a small part in this sellout of US jobs and the US worker
After communisms fall the US no longer had to play chess against a primary adversary USSR and to make sure that certain industries were kept at home for national defense and security reasons. So all the international trade wise guy lawyers and big corporations that could make money from sending manufacturing off shore began to do so. Also include all the hacks in DC who got bribes and campaign contributions for promoting the destruction of US industries.
It was his idea. Fact. As was a Free Trade Area of the Americas. Fact. And he kickstarted the negotiations that led to the creation of the WTO. Fact.
Protectionists, read and weep.