When I decided to write a column on Joe Biden’s cognitive decline and the many people who covered for him, I anticipated pushback from my more liberal readers. They delivered, in the thousands (of comments).

Wasn’t Biden a great president? Didn’t I know he’d just been diagnosed with metastatic cancer? Why kick a man when he’s down? More important, why pick on Biden? Wasn’t Ronald Reagan suffering from Alzheimer’s during his time in office? Isn’t the current occupant of the Oval Office — in addition to his many offenses against our democratic norms — acting a little addled?

This deflection is not good for the country or for the Democratic Party, which remains less popular than the Republican Party despite Trump’s erratic, cruel and occasionally unconstitutional policies. Democrats must rebuild trust with the public, and it’s not enough to shout “But what about Trump?” and hope the current president will do the job for them.

Nor is it true that Biden is just one of many presidents who were similarly diminished. Watch Reagan’s final news conference from December 1988 and you’ll see him give sharp answers to questions for a good half hour, something the Biden of 2024 couldn’t seem to manage for five minutes. As for Trump, a good deal of what he says is nonsense. But it’s mostly the same kind of nonsense he’s been spewing for years.

That said, it’s reasonable to worry about Trump’s cognitive capacity. People’s faculties often diminish sharply when they reach more advanced ages, and the decline can be sudden, which is why I’ve argued we need a constitutional amendment to impose a maximum age for the presidency. So Republicans need to ask whether they’ll do any better than Democrats if the president shows signs of serious impairment. It’s easy to proclaim what other families should do when it’s time to take Dad’s car keys away. But as generation after generation discovers, it’s also easy to put it off when it’s your dad who needs the intervention.

A political party is not a family, of course, but the loyalties can be almost as fierce. The people surrounding the president also have a financial stake in his success — cross the boss and touch off an embarrassing intraparty fight, and you can say good-bye to your salary, your future consulting contracts and your speaking gigs.

Should people in that situation put their country over partisanship, money and personal loyalties? Of course. But you’ll notice that Republicans didn’t when the question was Trump’s refusal to accept the 2020 election results. Sure, some did speak out for one evanescent moment when it appeared that Trump’s political career was over — at which point prominent Republicans issued thundering condemnations over the Jan. 6, 2021, Capitol riot. But when it became clear the family patriarch could not be easily retired, the family closed ranks.

Since 2021, I’ve had many conversations about that fact with Republicans. A portion of the party faithful sincerely believe the election was stolen. But explaining the reasons to believe the election wasn’t stolen doesn’t help. Because even if you can convince someone that a fraud big enough to swing the election would have left anomalous patterns in voting data that just aren’t there, they will simply retreat to the same excuse Democrats are offering for ignoring Biden’s problems: What about the other guys?

Okay, maybe our guy has some problems, but he’s the only one standing between us and the worst people in the world, which is to say, our political opponents. If we let them win, they will destroy our country. Sure, in ordinary times, maybe we could afford a political scandal that would divide our party, hand our opponents a political win, and maybe cost us the next election. But not when we’re fighting an existential battle for the soul of the nation.

All of which makes the sudden Republican piety about the Biden cover-up a little hard to swallow. Or, for that matter, Trump’s insistence last year that he would absolutely step aside as president if he has health problems.

But I try to give everyone the benefit of the doubt. Maybe the people salivating over this scandal are sincerely outraged that anyone could leave such a frail old man in charge of America’s nuclear arsenal. Maybe they truly believe it is impossible for any person of moderate intelligence to overlook the obvious signs of creeping senility. Maybe they know, deep in their souls, that when such a thing happens to the most powerful man in the world, there is only one decent thing to do: demand he vacate the office, and failing that, demand Congress remove him, no matter what the political or personal fallout.

If that’s what you believe, you have my heartfelt agreement, and one parting question: If those are your true beliefs, will you pledge now to live up to them?

Megan McArdle is a Washington Post columnist