Libyans celebrate the arrival of the rebels in Tripoli. (Alexandre Meneghini/Associated Press)

The West’s decision to intervene in Libya’s conflict is looking a lot shrewder in hindsight than it did just weeks ago.

As noted previously, the hard part in Libya is in many ways just beginning, for the rebels and for their Western backers. Meanwhile, the debate over American military action in a country with few U.S. national security interests isn’t over, either.

Still, one of the early lessons that might be drawn from Libya is that intervention may have worked because it was, in fact, limited. NATO’s mission was not open-ended, and the United States and its allies decided they would not deploy ground troops.

“One of the key lessons is that anybody who pretends that the choice is between doing nothing and a full-scale invasion. . . those people are putting a wrong choice before policymakers,” said Gerald Knaus, a co-author of a new book, “Can Intervention Work?”

Knaus, chairman of the European Stability Initiative, and his co-author, Rory Stewart, the British member of parliament, argue that limited intervention was in many ways the model for world powers when it came to intervention in the 1990s, and should be the model yet again.

Excerpts from an interview with Knaus below.

Checkpoint: When you look at Libya, what are the lessons we might take away?

Knaus: Libya in many ways is reminiscent of the successful and limited interventions of the 1990s. It’s very similar to what the United States decided to do, for example, in Bosnia in 1995. After three years of doing nothing and standing by, and watching the genocide and the war going on in the Balkans, the United States and its allies decided to tilt the balance in favor of one side against the other through airstrikes and through support. ... They put sufficient pressure on the Serbs to get them to the negotiating table to arrive at an agreement.

Following this, the United States and its allies decided to deploy troops for a very limited agenda. ... not even to build a nation but to help create time for letting peace take root and for some limited objectives to be achieved.

Libya was similar. The international community did not commit to an open-ended, overly ambitious agenda. The initial objective was to try to prevent atrocities. Nor did the United States and its allies declare in Libya that failure was out of the question — that one would be prepared to go to the very end, including occupation and invasion. This was, in fact, always off the table.

What was done successfully, without committing to total victory, was again to tilt the balance and then essentially make clear that whether Gaddafi would be overthrown in the end and how long it would take would be up to the Libyans.

This, in the end, worked as well in Libya as it did in 1995 in the Balkans.

Checkpoint: There are some who would say that this outcome could have come about a lot sooner had the United States and its allies used airpower more aggressively and if they had defined the mission as eliminating Gaddafi’s government. Do you think that would have been a mistake?

Knaus: I think the point is you never know in advance. But what is clear is that having a broad coalition was very important for the legitimacy of this intervention. That in general is the case. Successful interventions usually recognize that the regional context, the legitimacy of the intervention, the kind of allies you have on your side — even if it’s just there to lend credibility to your claim that this is not an invasion but a humanitarian intervention — all of this matters enormously.

So what we had in the Balkans and what we forgot after the string of military successes in the late 1990s, and in Afghanistan in 2001 as well, was that total involvement, huge deployment of forces and rapid victory can easily turn into defeat if they forget that the key to any solution is in fact having strong local allies and regional backing and legitimacy.

In Libya today, nobody can say that this was an invasion by the West or even that this was NATO defeating Gaddafi, even though NATO clearly played a crucial role in tilting the balance in favor of the rebels.

Checkpoint: What does that philosophy mean in terms of, say, Syria? What lessons can be applied to intervention there?

Knaus: I think one of the key lessons is that anybody who pretends that the choice is between doing nothing and a full-scale invasion — or as I think Charles Krauthammer put it at the beginning of the debate on Libya, “If you go to Vienna, you have to take Vienna or don’t go at all” — those people are putting a wrong choice before policymakers, which either leads to total inaction, which became extremely costly in the Balkans or in Rwanda, or indeed in Syria, or that you need to have open-ended military involvement that will necessarily lead to occupation and nation-building in the long term, which in most parts of the world is simply not an option.

We never know in advance how far we can go, because it ultimately depends on the motivation of local players. On the regional context, each crisis will be different, but if in Syria, there is a willingness to explore in an incremental fashion how you can put the most effective pressure on the regime now by bringing in some of Syria’s neighbors. . . then I think this kind of exploration should happen now aggressively.

In the book, we call it principled incrementalism. You do have the principled goal of trying to stop atrocities, but the tools you take and how far you can be prepared to go, you cannot define a priority from the very beginning.

Checkpoint: In Libya, these are still early days and as many have noted, there’s still a lot of work to do. The rebels are not in full command of Tripoli as far as we know. Even once they are, there needs to be the establishment of security and of government. How deeply involved should the United States and Europe be in Libya going forward?

Knaus: I think the way this intervention has happened, it allows the West to play quite a useful albeit still limited role, because there is now credibility on the side of the West. It has played an important role, it didn’t stand by. At the same time, this was a victory of Libyans, who paid a heavy price in terms of casualties, including in the last few days.

So I think it is clear that the impression which was avoided here — that this was imperial aggression — is crucial to now being able to effectively influence whoever arrives in power.

Any impression should be avoided that Libya is like Iraq or Afghanistan — that this is just the beginning of the deployment of Western troops or nation-builders.

Checkpoint: Skeptics might say that the United States and Europe have very limited interests in Libya, and that now that Gaddafi is gone, the rebels are there but they are going to require enormous support. At that price, is intervention worth it?

Knaus: One of the key factors that will enable us to have humanitarian interventions — limited military interventions in the future — is precisely that they are not seen as an automatic beginning of an open-ended, multi-annual mission that always ends in occupation, nation-building and the deployment of tens of thousands of foreigners. Recently, in the last 10 years, we’ve had a lot of intellectuals, policymakers argue. . . that unless you define a clear end state in which there is the full rule of law, in which warlords are disarmed, in which there is a functioning market economy — the kind of agenda Paul Bremer established when he arrived in Baghdad — you will not have stability.

Checkpoint: How hopeful are you that the Libya mission will establish a new precedent in which policymakers see the value of limited intervention?

Knaus: I think it’s useful to question some of the myths of the last 10 years. For example, the myth of what Richard Holbrooke did in the Balkans. Richard Holbrooke was very successful in the Balkans precisely because he always knew that both what the U.S. was willing to risk and what, as a result could be achieved, was limited. He did the best with the cards he was dealt — knowing for example that losses of U.S. soldiers would bring the mission to a stop.

Within such constraints, a lot was achieved. I think what we see now in Libya is a similar achievement with very clear constraints. There was no support within Europe or the U.S. for a very costly mission in which Western troops would be bogged down and take casualties. Within constraints, a policy goal was achieved — in fact, a series of policy goals. Gaddafi could not carry out his threat of mass atrocities, and Libyans were able to topple the regime.

If missions are interpreted in this light, we will not have the beauty of clear-cut victory. It will be more like a victory in the first Gulf War. There will always be those who will say much more could have been achieved if we only had gone in stronger in the beginning, if only we had stayed longer ... But in light of what happened in Afghanistan and in Iraq, and in light those efforts, hopefully we are beginning to doubt these theories and we are going to appreciate again that limited interventions are not only the only ones we are likely to sell to our own publics in the coming years, but are also the ones that are more likely to do some limited but decisive good in the countries in which we intervene.