“Men, women and children, they are ecstatic about the role of the coalition but worried that it may not continue,” he said.

Some Congressional critics complain that President Obama should have consulted Congress more thoroughly. Fair enough. But remember that the intervention was almost too late because forces loyal to Col. Muammar el-Qaddafi were already in Benghazi. Indeed, there was a firefight on Sunday right outside the hotel in Benghazi where foreign journalists are staying. A couple of days of dutiful consultation would have resulted in a bloodbath and, perhaps, the collapse of the rebel government.

Just before the airstrikes, Libyans were crossing the border into Egypt at seven times the normal rate. Once the strikes began, the exodus ended and the flow reversed. For all the concern about civilian casualties, Libyans are voting with their feet — going toward the airstrikes because they feel safer thanks to them.

Critics of the intervention make valid arguments. It’s true that there are enormous uncertainties: Can the rebels now topple Colonel Qaddafi? What’s the exit strategy? How much will this cost?

But weighed against those uncertainties are a few certainties: If not for this intervention, Libyan civilians would be dying on a huge scale; Colonel Qaddafi’s family would be locked in place for years; and the message would have gone out to all dictators that ruthlessness works.

The momentum has reversed. More airstrikes on Colonel Qaddafi’s artillery and armor will help. So would jamming his radio and television broadcasts. Arab countries are already delivering weapons and ammunition to the rebels, boosting their capabilities and morale. In short, there are risks ahead but also opportunities.

A senior White House official says that the humanitarian argument was decisive for President Obama: “The president was chilled by what would happen to the people of Benghazi and Tobruk. There were critical national security and national interest reasons to do this, but what compelled the president to act so quickly was the immediate prospect of mass atrocities against the people of Benghazi and the east. He was well aware of the risks of military action, but he also feared the costs of inaction.”

I’ve seen war up close, and I detest it. But there are things I’ve seen that are even worse — such as the systematic slaughter of civilians as the world turns a blind eye. Thank God that isn’t happening this time.