“He’s interfering with the chain of command, which is trying to police its own ranks,” said Peter D. Feaver, a specialist on civilian-military relations at Duke University and former aide to President George W. Bush. “They’re trying to clean up their act and in the middle of it the president parachutes in — and not from information from his own commanders but from news talking heads who are clearly gaming the system.”

Chris Shumake, a former sniper who served in Chief Gallagher’s platoon, said in an interview that he was troubled by the impact the president’s intervention could have on the SEALs.

“It’s blown up bigger than any of us could have ever expected, and turned into a national clown show that put a bad light on the teams,” said Mr. Shumake, speaking publicly for the first time. “He’s trying to show he has the troops’ backs, but he’s saying he doesn’t trust any of the troops or their leaders to make the right decisions.”