One of the most worrisome political signs for the Biden administration from the latest round of polling is that the president isn’t just losing support among typical swing voters—suburbanites, independents, anti- Trump Republicans—but he’s now starting to take friendly fire from his own base.

This vicious cycle is the political version of inflation, providing the White House few obvious tools to get out of the mess they’ve created for themselves. It’s a self-inflicted problem. Just as the president overstimulated the economy by pushing through $1.9 trillion in COVID stimulus, he inflated expectations among his supporters that he’d pass a transformative big-government agenda like FDR and LBJ.

He’s now dealing with a nasty hangover, with two centrist members of his own party blocking his Build Back Better social-spending plan along with a last-ditch effort to roll back the legislative filibuster to pass voting reform. He’s taking heat on all sides: Frustrated moderates facing tough reelections amid fierce political headwinds............