The United States is gripped by two interlocking constitutional crises: one spectacularly visible and noisy; the other unfolding more quietly. Senator Bob Corker’s Sunday remarks to The New York Times brought the quiet crisis into full public view.

The noisy crisis is, of course, the presidency of Donald Trump. The quiet crisis is the response of the national-security system to the noisy crisis.

“Mr. Trump poses such an acute risk, the senator said, that a coterie of senior administration officials must protect him from his own instincts. “I know for a fact that every single day at the White House, it’s a situation of trying to contain him,” Mr. Corker said in a telephone interview.”

This observation by the chairman of the Senate Foreign Relations Committee has been seconded by other insiders. “There are people inside the administration that think it is their job to save America from this President,” then-White House Communications Director Anthony Scaramucci told CNN’s New Day in July. In April, an unnamed senior administration official praised the work of Rex Tillerson, Jim Mattis, and John Kelly, then still secretary of homeland security: “They realize this is a tumultuous White House, and they are serving as a leveling influence over fractious personalities … responsibly protecting the country from enemies both foreign and domestic.” The “domestic enemies” in this formula apparently included much of President Trump’s own senior staff.