Do they have a safeguard against becoming like the US? By which I mean doubling down on core support base rather than seeking to convert opposition, and using populist rhetoric rather than traditional debate.
If not then it is only a matter of time. A new charismatic leader who says the right things emerges, and system is pushed to breaking point. The US might be the first, but Trump's lasting legacy will be proving to the world that politics can be played this way.
When people have 10 different ideological choices, it doesn't matter as much. I'm pretty sure that the Republican party would be represented by e.g. a Traditional Liberal party, a Conservative party, a National Conservative party, and perhaps small fascist party in any traditional European democracy. And that Traditional Liberal party would also contain a whole bunch of Democrats.
Yes, a multi-party system if far better. But over time, if the rhetoric is "if you aren't for us you're against us" and "a vote for SmallParty is a vote for Enemy" we trend towards two. We justify it to ourselves by saying that although we don't support everything OurSide says, it's far preferable to Them.
Yeah, in FPTP systems such as the American one, the effective minimum required share of the vote approaches 50% in competitive districts (and doesn't even matter in uncompetitive districts).
Meanwhile, in my country a political party only needs 2% of the vote to be represented in parliament and this will grant them approximately 2% of the seats since we use a proportional system. When people know that their votes likely won't be wasted, they tend to not vote tactically, preferring to vote on issues instead.
Anyway, I mostly hear people in FPTP countries (US and UK) talk about transferable vote or alternative vote, but AFAIK these are not really in common use. I think most of Europe uses the party-list system for proportional representation (https://en.wikipedia.org/wiki/Party-list_proportional_repres...).
I'm being an armchair politicologist here, but parties that do that tend to get isolated by the other parties, as a result don't get to govern, and as a result don't grow further. The fact that parties are destined to cooperate also forces them to tone down the "if you aren't with us you're against us" rhetoric.
Ironically, when NSDAP rose to power, this is how their competing parties neutralised themselves (according to what I remember from The Origins of Totalitarianism).
Large(r) parties generally cannot demonize (all) smaller parties all the time. Once you get to the election, you need somebody to go into a coalition with you so you get over 50% of the votes.
Obviously this applies only if your party has less than 50% of the votes, but in multi-party democracies its more unusual for one party to have 50% (or more) of the votes.
In a republic the head of state is usually directly elected; in a constitutional monarchy, the head of state is usually hereditary. Whether the head of state has any real power varies greatly.
The head of government (e.g. the prime minister) is most often NOT directly elected at all, since most multiparty democracies apply parliamentarism, i.e. the parliament has the power to select and remove the head of government.
So the voters focus on voting for parliament members and the head of government is INDIRECTLY elected by the winning _coalition_, so the head of government usually represents a coalition rather than a party. This a bit more dynamic as the coalition can change in between elections when parties realign, sometimes resulting in a new head of government or an early election.
when I said "their ideals and head of state" I was referring to the party, not the voters. I think what you wrote about coalitions in parliamentary system is useful for others, but doesn't add to our conversation. But to continue the discussion, my main counterpoint is that a coalition and coalition chosen head of state still dilutes what any particular voter wanted to happen, as opposed to satisfying at least 50% of the country at any given time.
I don't think it works too well with two-party systems. That is it is possible that head elected is only preferable to opposition, not actually to voters in general.
If not then it is only a matter of time. A new charismatic leader who says the right things emerges, and system is pushed to breaking point. The US might be the first, but Trump's lasting legacy will be proving to the world that politics can be played this way.