House Republicans, shaking off their post-recess stupor, are returning to Washington just in time for a familiar political crisis. Once again, hardline members of the G.O.P. caucus are threatening a government shutdown on September 30 if they don’t get their way—and once again they’ve placed a procedural gun to the head of Speaker Kevin McCarthy. “In order to appease them, Kevin’s gonna have to give them something,” a Republican source familiar with the state of negotiations told me, sounding understandably exasperated.

A few weeks ago, the Freedom Caucus released a list of grievances to be addressed in exchange for their support: the border crisis, the “weaponization” of government, “woke” policies in the military, etcetera. But momentum has coalesced around one demand, in particular: an impeachment, of somebody in the Biden administration, or perhaps even of the president himself. 

These demands were articulated most potently by Marjorie Taylor Greene, who told constituents last week that she would vote against a continuing resolution unless the caucus voted to stop funding Ukraine, eliminate Covid vaccine mandates, defund investigations into Trump and his allies, and begin the impeachment process. Caving on any one of those issues, particularly the impeachment topic—no matter how nakedly contrived or batshit crazy—could create a long term headache for McCarthy with Republicans in swing districts. He’s barely holding onto the majority by a thread; if he forces those 18 lawmakers in Biden districts to take too many uncomfortable votes, he could lose the House next year.