: The "mainstream liberals," check out this article.
I'm not sure what the definition of a "mainstream liberal" is, but unless liberals have been re-defined as right-wing or conservative, I'll cast my lot with the liberals, thank you very much.
While I admire Doug Henwood and subscribe to LBO, I don't agree that to have supported military action in the Balkans was somehow to betray liberalism (and my definition of liberalism is the one concerned with the protection of political and civil liberties, moreso than the protection of one's right to make a fortune). Given this, while I abhor violence, I do not see how it is reasonable for a strong nation or group of nations to stand idly by while a malevolent dictator engages in mass slaughter, as Milosevic did against the Kosovars. This is not to ignore the twisted history of the region, nor excuse past atrocities committed by the now-victims against the then-oppressors, but such distinctions are cold comfort to the civilians being raped and tortured and murdered. We had a moral duty to use force against Milosevic, though I do not think we ought to have bombed the civilians in Belgrade as a way of pressuring the Yugoslavian military.
Back to your main point: while mainstream liberals may not be as committed to social and economic justice as their more leftwing brethren, they are still further along that road than mainstream conservatives, so why belittle them?