Sometimes liberals are socialist allies, but despite the cries of idiot pundits, liberals are not socialists. They're just capitalists who wish capitalism was a tiny bit less cruel so they could enjoy what capitalism gives the rich. That's how it's always been. I wrote this elsewhere today:
I'm rereading Wheen's biography of Karl Marx, which has this, from Engels: "The fact is, au fond, that even these radical bourgeois ... see us as their future main enemies, and have no intention of putting into our hands weapons which we would shortly turn against themselves."
Liberals are still capitalists, and therefore they make dangerous allies for socialists.Which explains why the Democratic Party regularly teams up with the Republicans to make it harder for third parties to compete in US politics.
* I haven't decided if Robert Reich is a borderline socialist, but I love the guy, whatever he is: How a Few Private Health Insurers Are on the Way to Controlling Health Care