The killing of Muammar Qaddafi today puts an exclamation point on the Libyan revolution. Difficult challenges remain ahead for Libya. But with Qaddafi gone, his strange, formless, socialist-in-name-but-tyrannical-in-application form of government is gone as well.

The writing has been on the wall for months, at least since Tripoli fell to rebel forces. Since then, there's been plenty of writing on his legacy and impact on the world.

Long time Monitor Africa correspondent Scott Baldauf wrote in August that Qaddafi has had a profound impact on his continent.

"As the single-largest contributor to the budget of the African Union, a prime aid donor for poor African countries, and a dependable advocate for pan-African cooperation, Libyan leader Muammar Qaddafi is a man whose impact reaches far beyond his country’s borders. That impact is sometimes good, as when he funds hospital or road projects, or when his estimated 15 percent contribution of the AU’s budget allows the AU to send peacekeepers to Somalia, Darfur, and the Democratic Republic of Congo. And it can be bad, when he buys weapons for rebel groups to destabilize his neighbors like Sudan and Chad."

Writing for Brooking's soon after the uprising against Qaddafi began in February, Daniel Byman argued that sui generis nature of Qaddafi's Libya made looking to other countries for hints of Libya's future without him especially difficult.

"In any country, new regimes build on the institutions of old ones even as they create their own. For Tunisia and Egypt (and maybe for Bahrain, Yemen, and other countries being hit by the wave of unrest that is sweeping the Arab world), the new governments must contend with armies, judicial systems, and even political parties that began their life under the old order. But in Libya, these institutions are difficult to understand and their possible legacies even more difficult to anticipate. One of the (many) peculiarities of the Leader, as the Libyan dictator styled himself, is that he established a political system as bizarre as he is," he wrote. "Should Qaddafi go, Libya’s political structure must be rebuilt from scratch. It is not just a case of putting in a new regime, but instead of creating a new system from top to bottom. However, civil wars, as Libya is now in, are not known for creating an environment for that sort of restructuring."

In the US, there's been some talk of the NATO intervention as some time kind of model for future efforts to remove dictators.

To my mind, Libya presented a fairly unique set of circumstances – most important, that his population, in open revolt, was begging for assistance and it seemed that air power alone would tip the balance. That calculation by President Obama and European leaders proved correct. But the circumstances where that's possible are rare indeed.

Nevertheless, New York Times reporters Mark Landler and David Leonhardt write that Qaddafi's death "is another victory for a new approach to war."

"In the case of Libya — unlike in the case of the raids against Bin Laden and Mr. Awlaki — the United States made a clear effort to let other countries take a leading role. Indeed, Mr. Obama and his defense secretary at the time, Robert M. Gates, were initially reluctant to intervene and were lobbied to do so by, among others, the French. The biggest question now, though, may not be whether the new approach will become a model for other wars or whether it will help Mr. Obama politically. Instead, it is simply this: What will happen in Libya, the other countries that have been part of the Arab Spring and even in Pakistan and Afghanistan, which continue to be the sites of American drone attacks"