Republicans switching parties isn’t a good thing

What I run into occasionally in my facebook feed etc. are gleeful stories about some Republican or another switching parties because the GOP has become to extreme for him (so far, it’s always been a “him”, at least as far as I’m aware). And while I’m sure these stories are entertaining, and maybe even vindicate people in their opinion that the GOP has made an extreme shift rightwards, I don’t actually think this is a good development.

To explain this, let me backtrack a bit and first talk a bit about the U.S. political system and its parties a bit. The way voting is set up in the U.S. by its constitution, all of it is stuck at single-member districts in which candidates are elected to represent a region, not ideas*. As the wikipedia article notes, that tends to lead to two-party systems, with maybe an occasional 3rd party cropping up. Historically, in the U.S. 3-party situations tend to be unstable though and either an old party collapses, or the small 3td-party does, and either way you end up very quickly with only 2; and today even that much flexibility doesn’t exist, because the 2 parties are basically very rich and powerful political corporations, and the country is still suffering a 2000 election hangover and consequent allergy to everything 3rd-party. In other words, barring a complete collapse of the current political structure, the U.S. is stuck with the Republican Party, and the Democratic Party.
What this means in the context of Republicans leaving and becoming Democrats is that after all the “moderately” conservative people leave, the Republican party is not going to collapse under the mass of its epistemic black hole (at least not without causing the aforementioned collapse of the political structure), and the Democratic Party is not going to split into one moderately conservative and one progressive party**. Instead, by having people fall off the “left” edge of the Republicans and onto the right edge of the Democrats, the entire system shifts rightward even more, by making both parties just that little bit more conservative. And that’s just the obvious and immediate bad result. Another bad consequence is that when these former Republicans run for (re-)election, they will no longer be competing in primaries against other Republicans, i.e. people more to the right of them; they’ll instead be competing against Democrats, usually people to the left of them. That means whenever one of these guys ends up going into the general election, he does so instead of a more leftish candidate.

So what I’m saying is: unless these dudes have actually changed their minds and genuinely shifted leftwards rather than have the GOP shift rightwards away from them, I don’t want them changing parties; I want them to stay where they are and force the Republican party to be more like them and less like the teafucks. There’s nothing to celebrate when these guys change parties, because all that does is speed up the rightward shift of the US.

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* Although, my entirely non-lawyery reading of the U.S. Constitution failed to find a requirement for congressional districts voting for one representative; AFAICT the relevant parts (Article 1 Section 2; 14th Amendment Section 2) only say that the number of representatives would be determined by population in some way. For the states that currently have one representative this makes no difference, but there’s states with many representatives, and I’m not sure there’s a constitutional reason not to apportion a state’s seats proportionally after a state-wide election, rather than with district-level elections for a single representative.
OTOH, doing it that way would probably cause an even greater imbalance in the relative over-importance given to low-population states.
And while I’m at it, I’m not sure there’s a constitutional requirement for First Past The Goalpost voting, instead of preferential voting systems where you pick your top 3 candidates. Which could also help undo the 2-party-default, but are oddly unpopular at least in the media for some reason.

** Not that all people cheering at Republicans becoming Democrats necessarily think this, it’s just that believing something like that is one of a very few reasons I can think of to cheer this development. Some others I can think of are treating party politics like sports, and Rs leaving to become Ds means your team is winning; and thinking that Rs leaving means they’re becoming more moderate.