Call it the “Grandpa Simpson” presidency. 

Oldest-ever Commander in Chief Joe Biden this week gave the world some memorable mega-senior moments — and added yet more fuel to concerns he’s simply too feeble for a second term. 

At a joint UN speech, Biden went through a silent-movie comedy routine with Brazilian President Luiz Inácio Lula da Silva, walking smack into a giant flag as he entered and then fumbling with his translation headset as Lula spoke.

This prompted a question every American will sympathize with: “Can you hear me, President Biden?”

And Joe capped it all by shaking hands with the wrong man and snubbing Lula before bumbling blithely off stage.

Then it was off to campaign land, where he wowed listeners at a swanky party by repeating the same story about the 2017 Charlottesville riot prompting his decision to run against Trump nearly word-for-word, mere minutes apart. 

Pretty sure that’s the definition of “doddering.” 

And it’s hard to say whether it’s funny or sad. 

Especially since these flubs are only the latest in an endless series of malaprops, miscues, and meanderings that have X commentators snarking and Dems on a definite edge.  

Biden’s 80; if he runs and wins, he’ll be 82 when he starts his second term.

If he’s this gaga now, what’s he going to be like then? Or halfway through term two? 

Yes, there’s something comic about his blunders. 

But he’s auditioning for the most powerful job in the world, and mental acuity should be a key factor. 

Voters by and large know this: Per a recent WSJ poll, some 73% of registered voters (and a shocking two-thirds of Dems) say he’s too old to run again. 

Typically, the only ones who can’t or won’t admit this are Biden’s various press lapdogs (but what else is new?).

Then again, maybe we’re being too harsh and the prez can turn it all around — oh, no, wait: We’re getting word that President Biden has confused the Congressional Hispanic Caucus with the Congressional Black Caucus. 

Bring on the sad trombone . . .