I don’t find it remotely surprising that moderate members of both the House and Senate are balking at the size and scope of the budget reconciliation legislation that the Democratic leadership has put on the table. Nor does it seem surprising to me that the parliamentarian has ruled that a path to citizenship for the undocumented is beyond the scope of the Byrd Rule.

But beyond these small snags, the Biden legislative agenda is in peril, with centrist members objecting to huge swathes of Biden’s popular, poll-tested, revenue-raising ideas while also objecting to the idea of adding any debt. In essence, they are standing against any meaningful increase in the size of the American social safety net. And now Joe Manchin is saying the whole thing should be “paused” until 2022. Progressive members, seeking to avoid this outcome, have pre-committed themselves to the idea that they will sink the Bipartisan Infrastructure Framework if centrists do this, and they may well feel they have to fol…