They worry Trump has set a trap for himself by incessantly attacking Biden’s age and mental acumen. It’s a tactic the president has maintained even as his campaign publicly insists the former vice president is fully capable of a satisfactory performance. Unlike the president, who has spuriously claimed Biden is “probably” on performance-enhancing drugs, Trump campaign communications director Tim Murtaugh attributed Biden’s “quite good” performance in past debates to the Democrat’s ability “to turn it on when the cameras come” after years of experience in politics…

“The danger with [Trump’s] sustained attack against Biden’s cognitive abilities is that he’s now created a situation for himself where he has no excuse to fall back on if Biden lands a few punches and he struggles to return blows,” said a Republican close to the Trump campaign.

“I get why the president has gone after Biden for his age and gaffes — no reasonable person can ignore those things — but at some point he should have flipped the script to increase expectations heading into the debates,” this person added.