I’m going to sketch a model of what is currently going on in European and Anglosphere politics. It probably has some explanatory power; at the same time, there are weaknesses that I will mention. Very little of what is in here is original to me, so I should thank various people (mostly on Twitter) for the discussions leading to these ideas.
As most people with internet access know, the left-right spectrum is a poor measure of political positions. You can make it a bit more sophisticated by including two dimensions - one mapping the traditional left-right divide in economic terms, and one mapping social liberalism versus (for want of a better word) authoritarianism.
Due to the pressures of electoral politics - and especially the First Past The Post system - these two dimensions have tended to be bundled together in the form of an economically left-wing, socially liberal party (Labour, Democrats) and a pro-capitalist, authoritarian party (Tories, Republicans). This left people who are leftist plus authoritarian (call them “populists”) and who are right-wing plus liberal (“neoliberals” will do) without a clear party, and so they have tended to split between left and right largely according to personal preference.
Since the fall of Communism, though, the economic dimension has been becoming less important. It’s true that parties talk about increasing or decreasing regulation and redistribution, but fundamentally there has been an acceptance - especially among élites - that capitalism is here to stay. Meanwhile, the social dimension has been growing in importance, in particular due to the continuing influence of feminism and identity politics. One measure of this is that in the 1970s a book called A Theory of Justice could be primarily about the optimal amount of redistribution, whereas nowadays the phrase “social justice” is synonymous with LGBTQ+ advocacy. (Immigration may also have something to do with this: I suspect that it used to be viewed primarily as a social issue, i.e. “They’re criminals” vs. “That’s racist”, and is now seen primarily as an economic one: “They’re taking our jobs” vs. “But they’re also spending their paychecks and hence creating jobs”.)
This doesn’t mean that we shouldn’t model Blairites and Labour moderates as economically left-wing; however, it does mean that as compared to fifty years ago the distance between an élite leftie and an élite rightist is much smaller.
What this means is that you see increasing tension pushing for populist and neoliberal parties. In the UK the Labour Party is being taken over by dinosaurs who want to bring back genuine socialism but are at best unconcerned and at worst deeply regressive on social issues. The SNP are authoritarian in the truest sense of the word, and are to the left of the pre-Corbyn Labour party. In the US you have people like Donald Trump (a populist if ever there was one) and Bernie Sanders (who admittedly isn’t a proper socialist, but is still willing to describe himself as one). Tony Blair and his heir David Cameron are UK representatives of neoliberalism; Bill and Hilary play this role in the US.
The implication of this is that we are somehow likely to see a move over time towards having populist parties pitted against neoliberal parties. At this point I’ll note two caveats: (1) this is very vague and doesn’t offer anything like a timescale for predictions, and (2) it is likely to rely upon a corrupted meaning of “social liberalism”: are safe spaces illiberal censorship or just a way to respect oppressed minorities? If some Islamic communities force their females members to wear the hijab, practice gender segregation in public, and encourage homophobia, what is the socially liberal response?
Another thing to note is that in general, élites are fairly neoliberal. For the last thirty-five years or so we’ve had considerable success through left-wing governments tinkering with economy but massively reforming social institutions (e.g. Tony Blair) while right-wing governments have either been much the same (e.g. David Cameron) or have focused upon economic reforms (e.g. Margerate Thatcher). In some cases we’ve even had ostensibly left-wing parties delivering market reforms. But what happens if, through a change in the political system, all of the neoliberal élites end up in one party and that party isn’t in government? What if a Trump or a Livingstone actually gets into power? How well can democracy be restrained in such a case?
Some more problems which didn’t really fit in earlier: (1) How much of what I’m claiming to explain is just straightforward political polarisation, e.g. for reasons given by Jonathan Haidt in The Righteous Mind ? (2) Any account of UK politics should mention the EU. This one doesn’t, and what’s more this issue doesn’t fit the two-dimensional political map at all neatly. My impression is that orthodox leftists tend to be fairly pro-EU, but all three other groups are divided. (3) Even two dimensions isn’t that many. We could also include foreign policy, divide economic stuff into a regulation spectrum and a redistribution spectrum, etc.