When it comes to conversations about government spending, two subjects tend to get conflated. The first is an ideological debate about whether or not the government is in general any good at doing things. The second regards the actual effectiveness of specific things the government does. And the second conversation is far more concrete, productive, and important, which is why it drives me crazy when the first one prevents people from engaging the second.
Ron Haskins's new book is pretty wonky, but the articles he's written to promote it are quite readable.