>Which is to say, the various experiments and experiences we've run all point to the reality that the only stable state is one that's run on neoliberal principles (which is ideologically a rationalistic Rawlsian state and materially a state dominated by powerful, propertied interests). All others fail, from either internal or external competition.
What have been the experimental failures of social democracy and democratic socialism?
I'll take the societies of northern Europe that have established a large welfare state--at least relative to the Anglosphere--within a framework of capitalist economic institutions to be the (really only) representatives of social democracy. I don't really know anyplace that could be characterized as democratic socialism.
And... they're not bad off. If I could choose to be born anywhere under the veil of ignorance, they'd probably be my top choice. But I'd classify them as wholly neoliberal regimes. Even if you take issue with that characterization, at the very least, if you look at their governments over the past twenty years, they have moved sharply toward a more neoliberal program.
Which is the key point: at best, social democratic parties are mostly engaged in rearguard actions, trying to protect the best of what was built during the 20th century. Ideologically, however, they're adrift, having jettisoned pretty much everything they had, and their claim to governance always amounts to "we'll do neoliberalism better than the other parties!" Even then, more often than not they lose against opponents on the Right. Whatever you think of the ideology of social democracy, it's not offering anything new nowadays because it can't even imagine a world different from the neoliberal one we inhabit.
What have been the experimental failures of social democracy and democratic socialism?