The USSR had only one Party, but intra-party politics were all the more fierce as a result. I'm not saying that a full or even reasonably varied spectrum of true, non-spectacular or intelligent alternatives are being presented to the American voter. Just that what a 2-party system lacks in superficial variety it may more than make up for in internecine disagreement.
The ideological spread between Joe Manchin and AOC covers most of the ground covered by center and left European parties.
Most Americans don't have the option to vote for AOC or Joe Manchin (nor for their ideological equivalents). Neither for congress, nor for the President. They get shit candidates and still vote for them because the only viable alternative is an even worse candidate from a party you hate more than the other one. This is very much by design of FPTP, because it prevents third party competition from posing any threat to established parties. The two parties just pick their ideologies from a list of hot topics and never face any competition for the implementation of those ideologies.
This is very much not the case in more proportional voting systems, which provide true political competition across the political spectrum, not just superficial ideological posturing that isn't subject to competition. This is all very well known both practically and academically with tons of research to back it up. Youtube and wikipedia have all the mechanics, the references, and real world data, spelled out.
> Just that what a 2-party system lacks in superficial variety it may more than make up for in internecine disagreement
Sure, a political duopoly is better than a monopoly, but just like in other markets, only slightly so. Political power is a market like any other market, and needs significant competition from more than a couple actors to produce outcomes that are best for the consumers (voters). Even that AmEx case is a prime example, a direct result of shitty parties produced by this shitty election system. And that result will stay here for decades if not forever, regardless of which party is in power, because this election system is not going anywhere, and will keep producing such results.
I mean, San Francisco uses ranked choice and they ended up through a fluke with some District Attorney who everyone hates.
You may just want to consider that although you may not like the outcome, many voters do?
The House is there to represent people.
Both need to agree in order to get something done. This ensures that something that is passed is approved by a majority of people and a majority of states.
Otherwise, without this proposition, the states might not have ratified the constitution - the states predate the nation, and the nation is a union of states. This method of government is called "Federalism".
New Zealand has used MMP for 25 years and yet it still dithers between two major parties. Minor parties do tend to have to be incorporated into coalitions with one or the other major party, which is something, however, they’re almost always the same minor parties falling along the left right divide. Electoral systems do have an effect and they are setup to make it hard to radically change the system, however, they strengthen they don’t create the two party dynamic. Two major parties aligned with common human biases always seem to spring up when people are free to choose.
You are right that such changes are rare, they certainly don't happen once every 25 years, but the fact that they can happen is really important. Otherwise you are left with situations like current USA where many wants to vote for lower taxes but don't want to support Trumps other political views, in Europe you just vote for another right wing party but what do you do in USA?
Similarly you have many people who wants to vote for higher taxes and more government programs, but don't want to vote for all the identity politics. What should they vote for? Now the entire left is associated with identity politics and the entire right is associated with opposition to identity politics, making it hard to distinguish between different views and probably making the whole political conversation way more toxic than it needs to be. It has gotten to the point that people often assume you are racist if you argue for lower taxes etc.
MMP in NZ has increased competition and brought effective collaborative governments, and it hasn't even been 30 years.
(For reference, the Canadian House of Commons, according to Wikipedia's footer, divides into 158 Liberals, 119 Conservatives, 33 Québécois, 25 New Democrats, 2 Greens, and 1 Independent.
The Senate divides into 41 Independents, 20 Conservatives, 12 Canadians, 12 Progressives, and 8 non-affiliated, which last category raises interesting questions about the meaning of "Independent".)
It's worth noting that the American two-party system is explicitly protected by many laws that grant special privileges to "the two largest parties" or some similar category; it doesn't rely on the electoral system at all. If other parties got equal treatment before the law, you might see more of them around.
[0] https://en.wikipedia.org/wiki/First-past-the-post_voting
