Opinion | Trump Is Old. That in Itself Is a Risk.

What should we think as Donald Trump urges people to vote in January, confuses places and names, fumbles for words, simplifies his speech patterns, describes recent experiences that did not happen and in public seems increasingly vulgar, menacing and unfiltered?When President Biden showed his age and stumbled through the June presidential debate, I was among the first commentators to call on him to withdraw from the race.So what about the 78-year-old Republican nominee? Frankly, I wavered about writing this column, for there is an unfortunate history, notably during Barry Goldwater’s run for president in 1964, of using quasi-medical language to undermine candidates one disapproves of.

That is grounds for great caution.But if we’re trying to gauge a nominee’s fitness for office over the next four years, we also should acknowledge questions of Trump’s aging and capacity to do the job, as we did with Biden.It’s unarguable that Trump is acting even more erratically than he has in the past.

It’s also indisputable that Trump is at an age when many people see a physical or mental decline over the following four years.Perhaps one lesson from the Biden agonistes of this summer is that just as companies move C.E.O.s out before they struggle, we should be wary of electing elderly presidents from either party.Let’s acknowledge the risks of armchair analysis at a distance and note that Trump still has physical vigor and a defense against suggestions of cognitive decline: For decades, he has behaved outrageously and sometimes been rewarded for it.

And some people do not think Trump’s behavior is related to aging.Mark Esper, an honorable man who was Trump’s defense secretary and has criticized him as a “threat to democracy,” told me that Trump looks older to him but not obviously changed beyond that.Others do see significant change.“It’s hard to see how anybody thinks my uncle is still tethered to reality,” wrote Mary Trump, the former president’s...