Paul Krugman is worried about Ol’ Europe.

Europe has fallen short in terms of both fiscal and monetary policy: it’s facing at least as severe a slump as the United States, yet it’s doing far less to combat the downturn.

On the fiscal side, the comparison with the United States is striking. Many economists, myself included, have argued that the Obama administration’s stimulus plan is too small, given the depth of the crisis. But America’s actions dwarf anything the Europeans are doing.

The difference in monetary policy is equally striking. The European Central Bank has been far less proactive than the Federal Reserve; it has been slow to cut interest rates (it actually raised rates last July), and it has shied away from any strong measures to unfreeze credit markets.

The only thing working in Europe’s favor is the very thing for which it takes the most criticism — the size and generosity of its welfare states, which are cushioning the impact of the economic slump.

[…]

But such “automatic stabilizers” are no substitute for positive action.

Why is Europe falling short? Poor leadership is part of the story. European banking officials, who completely missed the depth of the crisis, still seem weirdly complacent. And to hear anything in America comparable to the know-nothing diatribes of Germany’s finance minister you have to listen to, well, Republicans.

But there’s a deeper problem: Europe’s economic and monetary integration has run too far ahead of its political institutions. The economies of Europe’s many nations are almost as tightly linked as the economies of America’s many states — and most of Europe shares a common currency. But unlike America, Europe doesn’t have the kind of continentwide institutions needed to deal with a continentwide crisis.

This is a major reason for the lack of fiscal action: there’s no government in a position to take responsibility for the European economy as a whole. What Europe has, instead, are national governments, each of which is reluctant to run up large debts to finance a stimulus that will convey many if not most of its benefits to voters in other countries.