Paul Mirengoff of the Power Line blog ponders the impact of age on the nation’s No. 1 deliberative body.

The Washington Post reports that the current U.S. Senate is the oldest in American history. Dianne Feinstein turns 88 this month. Charles Grassley turns 88 in September.

Richard Shelby is 87. James Inhofe is 86. Patrick Leahy is 81. Twenty-three senators are in their 70s. The average age of senators at the beginning of this year was 64.3 years.

It may be that being 88 now is like being, say, 78 a few decades ago. So despite being the oldest, this might not be the most age-impaired Senate in our history. Robert Caro’s book about the Lyndon Johnson-dominated Senate makes it clear that more than a few solons of the 1950s were rendered largely useless by age and/or drink.

Dianne Feinstein and some of the other Senators cited in the Post’s article insist they are still as sharp as a tack. But there must be a few who are losing it. A local pharmacist said in 2017 that he routinely sends Alzheimer’s medication to Capitol Hill.

In reality, it’s likely that most, if not all, of the Senators in their 80s and late 70s aren’t nearly as sharp as they used to be. To me, the interesting question is whether they realize this.

Most people I know in their 70s are constantly on the lookout for signs of mental impairment. I’m 72 and freak out if I can’t remember the fifth starter for the Arizona Diamondbacks.

Senators seem to be different. Maybe it’s because they are surrounded by staffers whose livelihoods, and in some cases mini-empires, depend on the boss believing he’s still fully fit to serve as senator. That’s one theory, anyway.

It’s not optimal to have a Senate with age-impaired members. Such a Senate denies fully effective representation to certain states and may function less fluidly than a Senate with 100 competent members.