Can someone explain why third parties seem so much more viable in the UK than US despite both using first-past-the-post single member districts? Is it like a historical difference or is there something structural?
A couple things. Most of the other parties are regionally based such as SNP, Plaid Cymru, and the N Ireland parties. Other than the Lib Dems no other party has stuck around that isn’t regionally based. So while there are a few Green Party MP s I would compare them to the occasional independents in
compare them to independents who occasionally win. Lib Dems is more interesting in that it consistently has seats and I think it’s because they occasionally serve in government so there is an argument they can be part of the government so essentially a Parliament changes the calculus slightly.
And coalition process means things happen after UK election which happen during US primaries. The Democratic party is a coalition stretching across a number of UK parties and in a place like NYC, the Dem primary is all that matters. In some UK constituencies Labour vs Lib Dem is all that matters.
