Pierce’s argument against letting Kasich deliver a prime-time endorsement of Biden is even more baffling. “The base hates him,” he insists, “and any Republican who is going to vote against Trump is already going to do so.” The first part of this statement is irrelevant — who cares what devoted Trump supporters think? — and the second part is obviously false. There are plenty of Republican or Republican-leaning voters who have serious qualms about Trump but also harbor reservations about the Democrats. The notion that all these cross-pressured voters have already decided irrevocably to support Biden is implausible on its face. Sarah Longwell has spent months studying wavering Republican voters. They definitely exist.

Even if the efforts to recruit Republican voters for Biden failed completely, why would any Biden supporters object? These transparently spurious complaints reflect the belief that the anti-Trump Republicans are morally unfit — by dint of their previous support for pre-Trump Republicans. Progressives suffer from a congenital tendency to demand that everybody who supports their side share all their beliefs. Conservatives didn’t complain when Democrats like Zell Miller and Joe Lieberman gave high-profile endorsements to the Republican candidate in 2004 and 2008, even though neither renounced every previous left-leaning position. Only Democrats seem actively hostile to accepting willing converts.

The second, more serious objection is that the Republican defectors are supposedly scheming to gain influence within the victorious Biden administration.