Andrew Greeley thinks so (via Conservative Green):

The United States is not much good as an imperial power because it lacks two of the qualities essential for effective imperialism: a population that is ready to absorb serious casualties in the cause of the empire and leadership that is sufficiently cynical to abandon moralism when there is a chance to deal.

It will do no good to lecture the American people on their obligation to endure substantial loss of life in a cause that the leadership thinks is a national duty. Americans will rise up in righteous anger if they have been attacked and destroy the foe, make no mistake about that — as the Japanese did in 1941. But they quickly become impatient with the endless, small wars, in which young Americans die without any clear purpose and without any “light at the end of the tunnel.”

That may be immature of Americans, but that’s the way we are. We lack the stern moral determination that the Wall Street Journal preaches to us several times a week. We are not exactly passivists, but we are isolationists. We always have been isolationists. Tell us that we must do something about Darfur or Kosovo or Rwanda and we ask: Why us? If the rest of the world is interested in doing something, OK, but don’t expect us to go it alone for long. After Korea and Vietnam, that should have been clear.

We went along with the Iraq invasion because our leaders were able to persuade us that it was a war to punish the Sept. 11 terrorists when in fact it was about the belief that a “democratic” Iraq would shift the balance in the Middle East.

I think it’s probably more accurate to say that people supported the Iraq war because they were convinced that Iraq posed a serious threat to our security. But beyond that, I think Greeley’s on to something here. In fact, this may be where the division between the elites and the rest of us that David Brooks was getting at may have some real traction. Despite disagreements over specific conflicts like Iraq, the one thing that our political elites agree on is repudiating “isolationism.” No major politician today would dream of running on a platform of “Come Home, America” as George McGovern did in 1972.

However, Greeley is, I think, giving short shrift to what’s been called America’s nationalistic “Jacksonian” impulse. This visceral patriotism is ready to kick ass and take names when necessary and believes in the essential righteousness of America and her ways. I think a lot of post 9/11 foreign policy gets its support from a union of this Jacksonian impulse among ordinary people with the technocratic globalism of the elites. True Jeffersonian isolationism is, I suspect, rarer than Greeley thinks. (See here for a clarifying discussion of various strands in America’s ideological DNA.)