How crazy must the President of the United States be before it’s considered cool to refuse an order? If the president orders an all-out nuclear attack on Canada, is the proper response “Yes, Mr. President,” or to throw the lunatic in a cell? —Knut Borge, Oslo

What does it take to remove a sitting president who is obviously mentally ill? I don’t think I need to say any more than that. —George D.

I’m starting to see a pattern: it’s almost as though readers have suddenly become preoccupied with the notion of a president being psychologically unfit to serve. The good news is a president’s civilian and military underlings can refuse to carry out illegal orders, and we likely have a constitutional procedure in place for removing a chief exec who’s no longer quite all there. The bad news? None of it’s likely to help.

The question of how the military might respond to an unlawful order from President Trump first arose before Trump had sewn up the nomination. At a February 2016 campaign stop, the C-in-C-to-be promised the crowd that to fight terrorism he’d bring back waterboarding and “much worse.” Former CIA and NSA director Michael Hayden countered that if Trump gave the order for torture “the American armed forces would refuse to act.”

Could refuse, sure. But would refuse?

Questionable orders tend to fall in a gray area. The recent attack on Syria, for instance, made without congressional authorization, could conceivably have been an unconstitutional exercise of presidential power, but who’s going to take a stand?

Disobeying a duly elected commander might look a bit like a coup, for starters, and any good soldier has to at least consider there may be some legit reason for a decision made above their pay grade.

When the Bush White House wanted to get into the torture business—i.e., do stuff that really was plainly illegal—the Justice Department simply reinterpreted the law to provide requisite cover.

Civilians might have more room to question their instructions, and more security: under the Whistleblower Protection Act, it is illegal to fire a civil servant “for refusing to obey an order that would require the individual to violate a law.” That doesn’t mean the Trump administration couldn’t find a subtler way to clean house or reward more loyal staffers.

But let’s say the prez becomes really erratic—i.e., in some way distinguishable from his SOP. How do we get him out of the driver’s seat? Impeachment is the best-known method, but its high-crimes-and-misdemeanors standard doesn’t apply in a case of mental incapacity.

Immediately after the election, though, talk began of invoking the 25th Amendment. The primary function of that amendment, adopted in 1967, is to ensure the presidential succession in case of death, but the fine print gets interesting.

Section four empowers the vice president, with the approval of a majority of the cabinet, to make a written declaration to the Speaker of the House and the president pro tem of the Senate that the president “is unable to discharge the powers and duties of his office,” upon which the VP can take over. This provision was written to cover situations, like the one following Woodrow Wilson’s stroke in 1919, where the president is out of commission but not dead.

Here the language is broad enough to include severe mental illness. If Trump became utterly disconnected from reality, Mike Pence and eight cabinet members could send a note to Paul Ryan and Orrin Hatch, and Pence would become acting president. The amendment’s machinery, however, gives Trump an opportunity to assert in writing that no, he’s fine (presumably a tweet would count), and retake the reins of office. Assuming the VP et al. persist, Congress has 21 days to vote on the matter; if two-thirds of each house see it the vice president’s way, the acting-president arrangement continues.

This procedure was considered at least once, in 1987. White House aide Jim Cannon, shocked at the disarray of the Reagan White House and the president’s listlessness, prepared a memo for Chief of Staff Howard Baker suggesting the 25th Amendment should be on the table. Baker didn’t laugh Cannon out of the room, but he didn’t buy the recommendation either.

And though we’ll never know for sure, Reagan may well have been suffering from early-stage dementia at the time. So I suspect we’ll be stuck with the current fellow for another 44 months minimum. Then again, if the ascent of Trump teaches us anything, it’s that predicting the future is a textbook mug’s game.