a lot of US liberals who backed Bernie were actually serious about the 'or bust' and jumped ship from the Democrats after. I've worked with, organized with, and even been roommates with some of them, amounting to a pretty good number just in my personal bubbles. A bunch of them are even communists now. And even more have been going that route since, including hugely now over this genocide in Palestine, which is seeing also mass sustained protests even outside of the Democratic Convention, which is happening alongside many defections. Liberalism is in the water from birth; most US communists on HB were once US liberals. It is the default slate before any other input. Saying liberals can never be convinced is demonstrably false because you're speaking contradictory negations about the literal experiences of many people on this very web site. It also doesn't serve the expanding of class consciousness or construction of socialist movement building to hold and push that idea, which I've seen many times on this site, which makes me laugh when I know it is coming from a US person who was, in all likelihood, a liberal just a few years before making such comments.