The Republican establishment began losing its party to Donald Trump on May 24, 2000, at 5:41 p.m., on the floor of the House of Representatives.

Urged on by their presidential standard-bearer, Texas Gov. George W. Bush, and by nearly all of the business lobbyists who represented the core of the party’s donor class, three-quarters of House Republicans voted to extend the status of permanent normal trade relations to China. They were more than enough, when added to a minority of Democrats, to secure passage of a bill that would sail through the Senate and be signed into law by President Bill Clinton.

The legislation, a top Republican priority, held the promise of greater economic prosperity for Americans. But few could predict that it would cause a series of economic and political earthquakes that has helped put the GOP in the difficult spot it is in today: with the most anti-trade Republican candidate in modern history, Trump, moving closer to clinching the party’s nomination.

“I try not to regret things,” said Sen. Jeff Sessions (R-Ala.), a Trump supporter who was one of 83 senators to vote for the China bill. “That’s one I regret.”