President Trump met with Bulgarian Prime Minister Boyko Borissov Monday for the prime minister's first visit to the White House of Mr. Trump's presidency. A senior administration official told reporters on a conference call ahead of the meeting, most of which took place behind closed doors, that the two would discuss how to help Bulgaria fight corruption and strengthen ties between the two nations.

But it was the president's decision to vindicate Navy SEAL Eddie Gallagher that took up the spotlight during the part of their meeting open to the cameras Monday. Mr. Trump pardoned Gallagher, who was accused of war crimes including murder but ultimately convicted by his military peers of the lesser crime of posing next to a corpse. Over the weekend, Navy Secretary Richard Spencer was forced to resign by Defense Secretary Mark Esper, who cited a private proposal by Spencer to the White House to allow Gallagher to retire and remain a SEAL. Esper confirmed Monday that the president ordered him to let Gallagher keep his Trident military pin.

Mr. Trump continued to defend his defense of Gallagher on Monday, reiterating his allegiance to U.S. troops. The president insists that members of the U.S. military need to be allowed to fight, and not worry about the consequence.

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"With Eddie Gallagher, you know that story very well," Mr. Trump said. "They wanted to take his pin away and I said, 'No you're not gonna take it away.' He was a great fighter. He was — one of the ultimate fighters. Tough guy. These are not weak people, these are tough people. And we're gonna protect our war fighters."

Senator Jack Reed, the top Democrat on the Senate Armed Services Committee, declared the president's intervention over the weekend "outrageous" and "irresponsible."

"This was an outrageous, irresponsible interference by President Trump in the military justice system," Reed said in a statement on Monday. "The White House's handling of this matter erodes the basic structure of the military and the basic function of the Uniform Code of Military Justice."