This would be the biggest gift of all to Vladimir Putin.  The New York Times is reporting Donald Trump has suggested to senior administration officials that the U.S. should withdraw from NATO.  From The Times:

“Last year, President Trump suggested a move tantamount to destroying NATO: the withdrawal of the United States.

“Senior administration officials told The New York Times that several times over the course of 2018, Mr. Trump privately said he wanted to withdraw from the North Atlantic Treaty Organization. Current and former officials who support the alliance said they feared Mr. Trump could return to his threat as allied military spending continued to lag behind the goals the president had set.”

The move was seen as disastrous for the United States by top aides and would, as the Times writes, embolden Russia for decades in Europe.

“Now, the president’s repeatedly stated desire to withdraw from NATO is raising new worries among national security officials amid growing concern about Mr. Trump’s efforts to keep his meetings with Mr. Putin secret from even his own aides, and an F.B.I. investigation into the administration’s Russia ties.”

NATO is a group of 29 countries in Europe and North America.  It was formed after World War II to keep the Soviets in check.  It grew after the end of the Cold War to include several former Soviet satellite countries.