Professor Munger nails it
He takes Liberals to task for one of their favorite rhetorical devices:
Good Lord. We learn once again that if you take large amounts of resources from their highest valued uses, and give those resources to Person A, then Person A will, in general, be better off. This tells us very little about whether it's a good policy, of course. But these folks don't really care. The point is that "But it helps Person A!" is not really a complete argument, so it's not worth refuting (it's also not possible to refute, because it's not actually an argument).
I'd quibble that while it might not be worth refuting, it is worth pointing out every darn time they do this.