It's yet another demonstration of how ineffective electoralism is at stopping fascism. The Democratic Party is centrist (or center-left if we're being generous). Centrism isn't really an ideology, just a strategy for winning elections. Principles are just tools to be either used toward that end, or discarded. It does tend to be pretty effective, which is why it's so prevalent.

Fascists, however, are committed to gaining power *by any means necessary*. While centrists are constrained by rules and norms, fascists have no such limitation. By discarding any moral restraints, fascists become far more effective at the centrist strategy than centrists could ever hope to be. In turn, the centrists are forced to double down on discarding any principles that they may have grown attached to, following the lead of the fascists in an attempt to catch up.