Inside Donald Trump’s Shadow Presidency

In the years since he left the White House, former President Donald J. Trump has remained a force in international politics, meeting with a number of foreign leaders and operating out of his Mar-a-Lago estate in Florida.

When Finland wanted to join NATO to ward off Russian aggression, it knew it had a friend living in the White House and could count on President Biden’s support. But to ensure that the U.S. Senate would ratify its membership bid, Finland’s government decided to also seek out the president living in Florida.

And so Mikko Hautala, the Finnish ambassador to the United States at the time, made a point of speaking privately with former President Donald J. Trump to persuade him of the merits of his country’s joining the alliance. The goal was to head off any opposition by Mr. Trump, who has long been openly hostile toward NATO.

The strategy worked. Mr. Trump, who potentially could have ignited Republican opposition with a single intemperate social media post, remained publicly silent, and the Senate voted 95 to 1 to approve Finland’s admission to the alliance in August 2022. Had Mr. Trump spoken out against the move, it would have taken only 34 votes to block the two-thirds supermajority needed for ratification.

In the nearly four years since he left the White House, Mr. Trump has acted as something of a shadow president on international affairs operating out of what he used to call the Winter White House at his Mar-a-Lago estate in Florida. Even before he kicked off a comeback bid to reclaim his old office, foreign governments realized that Mr. Trump was still a force in American politics and that they needed to take him into account in their dealings with the United States.

Now that he is the Republican nominee for president in next month’s election, foreign leaders have been playing up to Mr. Trump even more. A parade of world leaders has made the pilgrimage to Mar-a-Lago or to Trump Tower in New York, including the leaders of Ukraine, Israel, Poland, Hungary, Argentina, Qatar, the United Arab Emirates and other countries. The crown prince of Saudi Arabia rang up Mr. Trump’s cellphone. The newly elected prime minister of Britain dropped by last month for dinner.

“Very unusual for a former president,” said Jeremy Shapiro, a former State Department official who is now director of the U.S. program at the European Council on Foreign Relations. “I suppose it comes from his status as both a former and possibly future president, which is of course unique.”