Robert Lane Greene has a good piece in the New Republic on European anti-Americanism and how it's related to their own struggles in forming a cohesive European super-state.

It is against this backdrop that Europe's current tense relationship with the United States, typified by its criticism of American policy towards Iraq, must be understood. Sluggish economies, institutional confusion, and distant elites have helped maverick and xenophobic parties (most of which loathe the EU itself) score victories in recent years in Austria, France, Denmark, Sweden, and the Netherlands. To defuse this growing threat without addressing its own malaise, the European political class increasingly changes the question from "What's wrong with Europe?" to "What's wrong with America?"

He goes on to admit that European criticism of America is generally a good thing, but as with any criticism, if it is intended to break down, instead of to improve, or if it is merely an exercise in frustration with one's own problems, meant to divert attention away from domestic issues, it overstays its usefulness.

To be fair, Europe's criticism of American policies is not necessarily a bad thing. No country is entirely virtuous, and Europe occasionally functions as a useful loyal opposition, moderating some of America's more extreme urges. (It was largely European pressure, after all, that forced the United States to pursue a Security Council resolution on Iraq.) But an opposition must do more than criticize--it must also present an alternative. What's the European alternative on, say, security policy? Multilateralism? This is a means, not an end. Respect for human rights? It took the American-led NATO to act decisively in Europe's own backyard and bring an end to bloodshed in Bosnia and Kosovo. Until Europe can demonstrate that it stands for something positive and coherent, its routine opposition to the United States will be too easy to dismiss as cynical political calculation. And rightly so.

This is true of any criticism. There comes the inevitable point where the critic must put up or shut up. That is, they must provide an alternative to the status quo and adequately defend its merits.

Otherwise, the critic takes on the absurd posture of a court jester, jeering and poking from the sidelines without offering anything substantive to take the place of what's being done.

The most telling condemnation of such blowhards is to simply, pointedly ask them, "What would you propose?" If you are greeted by the stunning sound of silence, you'll finally know exactly what's going through their heads.