President Trump discussed pulling the U.S. from NATO.

On multiple occasions last year, the president said that he wanted to withdraw the U.S. from the 69-year-old North Atlantic Treaty Organization, senior administration officials told our reporters, revealing highly sensitive efforts to preserve the alliance.

Such desires underline concerns about Mr. Trump’s secretive relationship with Russia and its president, Vladimir Putin. Withdrawing the U.S. from NATO would be a grand victory for Mr. Putin and effectively destroy a 29-country alliance that undergirds the E.U.’s security and the world order, and senior administration officials were at first unsure if Mr. Trump was serious. He was, and so his national security team scrambled to run interference and keep the U.S. in.

Mr. Trump’s belief that NATO is a money-loser appears to be fundamental to his worldview, along with an often-stated desire to seize Iraq’s oil, officials said.