Brad DeLong sees the light (almost)

Brad DeLong writes that "the core problem of modern liberalism" is "how can one support the idea of an activist government when half the time that government will be run by malevolent or incompetent Republicans?

I agree with but the change of one word. "Republicans" should be replaced with "politicians." Change that one word and you move from a naive, partisan view of the world to a principled, non-partisan and correct view. Note that it is not necessary to believe that every politician is a knave or even that half of them are. The core problem is that knaves can do much more harm than angels can do benefit. Constraints on government ought to be written, therefore, on the worst-case scenario. David Hume, of course, said it better than I.

Political writers have established it as a maxim, that, in contriving any system of government, and fixing the several checks and controls of the constitution, every man ought to be supposed a knave, and to have no other end, in all his actions, than private interest. By this interest we must govern him, and, by means of it, make him, notwithstanding his insatiable avarice and action, cooperate to public good.... It is, therefore, a just political maxim, that every man must be supposed a knave; though, at the same time, it appears somewhat strange, that a maxim should be true in politics which is false in fact.

David Hume, "Of the Independency of Parliament", in Essays Moral, Political, and Literary.