It wasn’t that long ago that everyone was talking about the “libertarian moment” in the US. Now, libertarianism/propertarianism is pretty much dead. The support base, advocacy groups and so on have gone full Trumpists, while the intellectual energy has shifted to “liberaltarianism” or, a more recent variant, Tyler Cowen’s conversion to “state capacity libertarianism“.
Most of those departing to the left have mentioned the failure of libertarianism to handle climate change. It was critical for two reasons. First, any serious propertarian response would have required support ofr the creation of new property rights (emissions permits) and the restriction of existing ones (burning carbon). That would imply an acknowledgement that property rights are not natural relations between people (owners) and things (property). They are socially constructed relationships between people, allowing some people to use things and to stop other people from doing so. Second, the effort to deny the necessary implications of climate change inevitably resulted in denial of the scientific evidence that climate change was occurring. That contributed to a situation where most former libertarians are now Trumpists, happy to deny the evidence of their own eyes if that’s what the leader requires of them.
I’m working on a longer article spelling all this out. In the meantime, comments welcome.