Is the US developing an informal form of party discipline?
In US elections, candidates are elected individually. However, most recent elections track closely with each other in terms of partisan vote choice.
The reason this is relevant is in the past, there were local parties with large differences to cater to the ideological lean and social circumstances of their areas. But that has largely disappeared and state parties are mostly arms of national parties.
Congresspeople who vote party line usually win primaries unopposed or very easily but do not do so enough usually face primary challengers. Examples:
- Pro Trump impeachment Republicans are facing primary challenges.
- Joe Manchin and Kyrsten Sinema are facing heavy criticism for not voting for certain more ambitious Democratic proposals.
- Some Senate Republicans are criticized for voting for Biden bills especially the infrastructure one.
Party discipline is the idea that if most of a political party's base/members favors a certain legislation or idea, every elected representative should support it because it is their duty. The United States does not have this directly.
But I want to know if this seems to be developing in the sense that members of Congress who buck the party trend like Krysten Sinema are criticized, mostly by their own party. I'm thinking about primary elections being the biggest mean to enact party discipline. The big difference is that this type of what could be thought of as party discipline is usually enacted by voters not simply leaders of parties.