The Monitor asked a leading US foreign policy expert, Walter Russell Mead, to place neoconservative beliefs in historical context.

Which leaders in US history would be neocons today?

It's possible that Teddy Roosevelt would be a neocon. I think it's almost certain he would have supported the war in Iraq. And he wouldn't have cared about the lack of a UN resolution. I'm not sure who else would be a neocon in foreign policy. In some ways [neocons] are very original.

Is there a particular point in the history of US foreign policy that reminds you of today's foreign policy environment?

In some ways, it reminds me of the period around 1946-47 when we were trying to figure out what the cold war was going to mean. The country realizes we have a challenge on our hands, but we're not quite yet sure how we're going to meet it ultimately.

There's also the period in the early part of the 20th century when it was clear that the British empire was not going to be as strong and the United States was growing. And you had people like Teddy Roosevelt and others beginning to think ... "What if America is going to become an imperial nation? What does that look like?"

What makes neocons unique throughout the history of US foreign policy?

When we think of Wilsonianism now, we tend to think of secular, humanist ideas - building a world government - sort of a Europeanist foreign policy. If you went back a hundred years or so, Wilsonianism was carried out by people like missionaries who thought that the way to make America safe was to make the rest of the world believe the way we do and act the way we do. But they weren't as concerned about the institutional aspect.

The neocons of today have sort of revived this older Wilsonian tradition. They are no longer concerned, say, about the United Nations, which is what we think Wilsonians are mostly thinking about ... or the World Court. In fact, they think that stuff gets in the way to some degree. But they are more concerned about basic American values and spreading those.

So it's a different Wilsonianism from what we've all grown up thinking about. It's non-institutional and it's values-based. To some degree, it's a conservative Christian value base. Even though many conservatives are Jews, the sort of basic values that they are promoting are very much the sort of Protestant, Christian values that were dominant in 19th-century America.

Do you think neoconservatives have had their "moment in the sun" with their successful push for a preemptive war against Iraq? Do you think that the broad support they might enjoy now will wane?

I think they're still in business. The weak spot, obviously, for them, is that ... if we are taking 20 casualties a month in Iraq a year from now, there may not be a lot of people thanking them for this. But, on the other hand, we were in the [Vietnam War] for years before people really turned against it. And even then, I think ... other than elite opinion ... the thing that bothered most ordinary Americans wasn't that we were fighting or that our strategy was too hawkish, but they couldn't see that we had a strategy for victory ... that it looked like it was going to be a deadlock forever.

It may well be that if the American people remain convinced that the war in Iraq is necessary for national security ... and even if the war goes on for a long time ... if they feel that we have a strategy that will win and that is necessary, people may support it for a very long time. It's hard to say. If it goes well, even after a while, the neoconservatives will be strengthened.

What would be some other factors that would put the neoconservatives out of business, or enhance their standing even more?

I think failure is always bad.... If the public judgment is, "We took their advice and we've ended up in a hell hole," then we won't be asking [neocons] for advice for a while. I think it's the public judgment on the success of the policies that they've proposed.

Where does world opinion factor into this?

Probably not very much. Except if you reached a point where the unpopularity of American foreign policy was in some way making it impossible for the US to conduct the policy that it wanted to. It's hard for me to see how that would happen.

What do you see as the neocons' biggest obstacles in the future?

They have the problem that all Wilsonians have. Wilsonians always want more foreign policy, in a way. If you think about democratizing the Middle East ... that's an incredibly tall order. That could take us a very long time. And it's not completely sure that everybody in the US is going to want to make those sacrifices ... especially if it involves troops, maybe not just in Iraq, but in other places ... some of whom will be getting shot at from time to time.

• Walter Russell Mead is a senior fellow at the Council on Foreign Relations.