The messy 24 hours were part of a week in which the West Wing has erupted with an all-guns-firing-at-once frenzy intended to prove that Mr. Trump is an effective leader on the cusp of his 100th day in office. His staff has been alarmed by a trend: A decreasing percentage of Americans, even supporters of Mr. Trump, view him as capable of executing on his muscular if vague campaign promises.
The Nafta confusion has its roots in the 2016 presidential campaign, when Mr. Trump promised repeatedly that he would either renegotiate the 23-year-old agreement with Mexico and Canada or withdraw from it. It was a theme that resonated deeply in the economically struggling parts of the country where Mr. Trump is the most popular.
By the time Mr. Trump was in the White House, his more moderate advisers — including Gary D. Cohn, his top economic adviser, and the president’s son-in-law Jared Kushner, who communicates regularly with President Enrique Peña Nieto of Mexico — had persuaded him to temper his attacks on America’s trading partners. But hard-liners like Peter Navarro, the president’s chief adviser on trade, were pushing for a strong statement on trade to close out Mr. Trump’s first 100 days.
Administration officials planned a meeting for Wednesday evening on withdrawing from Nafta. Before it was held, some officials told reporters that Mr. Trump was likely to withdraw from the deal. It is not clear whether the officials were reflecting what they thought was going to happen, or whether they had agendas — either to try to lock Mr. Trump into the decision, or to try to create a firestorm that might persuade him not to withdraw.
In any case, the news went viral.
Congressional Republicans and business leaders urged Mr. Trump to reconsider. Senator John McCain, Republican of Arizona, called the idea a “disaster.” The Business Roundtable, which represents large companies and is led by Josh Bolten, a former White House budget director and chief of staff to President George W. Bush, said that “we strenuously oppose withdrawing” from Nafta. The Mexican peso plummeted.
At the White House, Mr. Trump’s moderate advisers urgently tried to convince him that even a first step toward an exit — his executive order would have begun a six-month waiting period before the United States could actually withdraw — could cause significant economic disruptions in all three nations, whose economies are increasingly intertwined. Sonny Perdue, Mr. Trump’s agriculture secretary, brought a map to the Oval Office showing the areas of the United States that would be hardest hit.
American farmers sold $2.6 billion of corn to Mexico last year, and American agricultural exports to Mexico have increased 64 percent over the last decade. Under Nafta, Mexico cannot charge tariffs on those imports, but if Nafta goes away, Mexico could immediately restore a 37 percent tariff on American corn. On Wednesday, as news of the potential executive order circulated, corn futures dropped 1.3 percent.
“Mr. President, America’s corn farmers helped elect you,” Wesley Spurlock, president of the National Corn Growers Association, wrote in an open letter to Mr. Trump. “Mr. President, agricultural and rural America are counting on you. We urge you not to withdraw from Nafta.”
By 7 p.m., Mr. Peña Nieto was on the phone. He told Mr. Trump, according to Mexico’s foreign minister, Luis Videgaray, that he shared a desire to begin trade negotiations as soon as possible. But Mr. Peña Nieto also emphasized that he was “looking for a negotiation that is good for Mexico, a win-win.”
Mexico, like Canada, already agreed to substantial changes to Nafta as part of the now-discarded Trans-Pacific Partnership, a broader trade agreement negotiated by the Obama administration that would have supplanted the older deal. Among those changes: increased protections for workers, like the right to unionize; enforceable environmental protections; and rules for digital commerce. Those changes would generally increase the cost of business in Mexico, insulating American companies and workers from competition.
Mr. Videgaray later told reporters that in his view, Mr. Trump’s talk of withdrawing from Nafta might have been an effort to prod Congress into action. The White House wants Congress to authorize expedited approval of a reworked agreement — a process known as trade promotion authority — but so far, it has not been able to win support from congressional Republicans. Wilbur Ross, the commerce secretary, said Tuesday that talks with Congress had “stalled.”
The call from Mexico was followed by one from Prime Minister Justin Trudeau of Canada, who also urged Mr. Trump to focus on negotiations. “Nafta has been improved a dozen times over the past 20 years, and we’re happy to sit down and talk about how it can be improved now,” Mr. Trudeau told reporters in Saskatchewan on Thursday. He said he had told Mr. Trump that ending Nafta would cause “a lot of short- and medium-term pain for an awful lot of families” on both sides of the border.
By 10:30 p.m., the White House had issued a statement saying Mr. Trump would not pull out of the deal for now. By Thursday morning, Mr. Trump was busily posting on Twitter, saying he had agreed to pleas from the leaders of Canada and Mexico not to withdraw immediately. But he reiterated that he would still pull the United States out if he could not negotiate a better deal.
“I received calls from the President of Mexico and the Prime Minister of Canada asking to renegotiate Nafta rather than terminate,” Mr. Trump said on Twitter. “I agreed…”
Moments later, he continued, “…subject to the fact that if we do not reach a fair deal for all, we will then terminate NAFTA. Relationships are good — deal very possible!”
That brought Mr. Trump right back to what he had said all along.