The commentary on the president’s course in Libya has been instinctively adversarial. Much of the press may be compensating for its cheerleading or supine acquiescence in the fraud of the Iraq War. So reporters chase administration officials around briefing rooms and TV studios, pressing questions that can’t be answered at all (about operational details), or can’t be answered candidly — for example, about the targeting of Moammar Gadhafi. On both sides, partisans join in — some Democrats apparently against any conflict anywhere — and Republicans who never questioned Bush, Cheney, or Rumsfeld, but somehow would scorn Obama even if he got Iran to surrender its nuclear weapons.

Having forged a genuine multilateralism on Libya and pulled off the miracle of no Chinese or Russian veto in the Security Council, the administration now has to speak diplomatically while wielding big missiles. But through the white noise of the media and political scrum, some truths ought to be clear even if Obama and company can’t clearly say them.

First, why did Obama dither?

He didn’t. He was waiting until conditions were right and perhaps hoping, at least at first, that the rebels would win on their own. The president did lean forward, announcing that Gadhafi had to go. John Kerry wrote an early op-ed advocating a no-fly zone.

Imagine if Obama had gone to Congress this time. In the Senate, Rand Paul would have filibustered while Benghazi burned.

Too much of the internal debate — and credit-claiming from insiders — ended up on the front pages. But all along Obama kept all options on the table. At about the time any prospect for unaided regime change was being rendered forlorn, the Arab League took the unprecedented step of asking for outside intervention. Now Obama could exercise the option of force without risking America’s standing — and vital interests — in the Middle East. Would that George W. Bush had dithered instead of dissembling America into a war where the first casualty was truth, and the toll is measured not only in lives and dollars, but in diminution of our moral authority and global influence.

Second, why engage in yet another conflict in a Muslim country — and can we afford it? This line of questioning is both superficial and hypocritical. Superficial because one bad war in Iraq and one badly fought war in Afghanistan don’t constitute a reason to reject action when and if it’s right in Libya. Hypocritical because complaining about the relatively modest cost of that action comes with ill grace from those in Congress who over the past decade didn’t care about spending a trillion dollars (and the total’s still climbing) on the wrong war, in the wrong place, at the wrong time.

Third, didn’t Obama violate the Constitution by not going to Congress for a resolution or a declaration of war? I have three words for the critics here: Grenada, Panama, Balkans. Ronald Reagan, the first Bush, and Bill Clinton didn’t wait on legislative approval before invading two countries and bombing Belgrade when they decided the issues were urgent and the cause was just. Indeed, the last Declarations of War came against the Axis powers. Since Korea, presidents have acted again and again without either a formal declaration and often without any form of explicit legislative approval. Imagine if Obama had gone to Congress this time. In the Senate, Rand Paul would have filibustered while Benghazi burned. And perhaps the unserious Dennis Kucinich would have insisted on establishing his Department of Peace as Gadhafi slaughtered thousands. Enough said.

Fourth, why intervene in Libya, but not Yemen or Bahrain? The question reflects a simplistic equivalence that ignores a fundamental reality: Despite the rhetoric of universalist democracy, effective foreign policy demands a balance between our interests and our ideals. In Bahrain, a longtime ally at a strategically important location on the Arabian Peninsula, the conflict is at least as sectarian as it is political. It would be a disaster to have one free election there where Shiites sympathetic to Ahmadinejad and the ayatollahs would prevail and then close the process down, allying or ultimately even merging with Iran, which covets Bahrain as just another Iranian province. This wouldn’t be democratic in any true and lasting sense. That’s something else Obama can’t say, so he urges a process of peaceful consultation while Saudi Arabia dispatches troops to restore order. Maybe, just maybe, there will be some incremental progress toward wider political participation. But Bahrain isn’t Libya — and the pursuit of American values can’t be a heedless exercise that vitiates American interests.

To accept a balance between interest and ideals isn’t comfortable, but the world is complicated. In the 1980s, William F. Buckley Jr. once asked me why we liberals wanted to be so tough on human rights with nations like El Salvador, but not equally confrontational with the Soviet Union. I answered that on El Salvador, we should do it because we could. The small difficulty we had to take into account when dealing with the Soviets was that they had nuclear bombs — and we could only push so hard without creating an existential threat. Each situation has to be judged circumstantially; today, a 180-degree turn in Bahrain, followed by the destabilization of Saudi Arabia, would be a catastrophe on all counts — for the global economy, for U.S. security, and even for any prospect of peace in the Middle East.

Fifth, what’s our vital interest in Libya? And why not just let Gadhafi impose his reign of terror? This is a case where morality and realpolitik coincide. The president, like France’s Nicolas Sarkozy and Britain’s David Cameron, had said it was time for Gadhafi to go. (Actually at least five American presidents have said that.) Firmly back in power — and he was on the brink of that on the eve of the West's bombing campaign — Gadhafi would be a mortal enemy, an incubator of terrorism, an unpredictable madman who would hate the United States, the West, and his Arab neighbors — and harm them and us in any way he could.

So the intervention is not merely about saving Libyans, although that’s a worthy purpose, but about our own national security. Simultaneously, it enhances our credibility and our long since shattered popularity in the Arab world. Who ever thought we would see the day when an American pilot shot down over an Arab country would be rescued and cheered by local villagers hailing the United States not as an adversary, but as a last, best hope?

Finally, will this work, and how? Why has Obama ceded leadership to the French and British without clear lines of authority? Is the no-fly zone enough? Are we willing to let Gadhafi stay in power — or is he a target? There are plain answers to all of these questions — but they can’t come from the administration — at least not yet.

The United States is a driving force here, but it’s better for us that we not be seen as such. Multilateralism can be messy, but the details of the command structures will be resolved. By the way, ask Gadhafi’s forces if they sense no clear lines of authority as the cruise missiles rain down.

They also know all too well that this intervention involves not only a no-fly zone, but an assault on their troops and tanks on the ground. When Bill Clinton launched an air campaign in the Balkans, we were warned that air power alone wasn’t enough — that it would never dislodge the genocidal Slobodan Milosevic. It did, and he was being tried for war crimes in The Hague when he died.

As for Gadhafi, our objective — the only acceptable outcome — has to be regime change. The president can’t say that either, because the U.N. resolution doesn’t; that was the price of diplomacy. But surely this can’t constrain the final outcome. And of course, Gadhafi ought to be a target even if a U.S. general says he isn’t — and that we simply bombed his fortress to knock out military communications, not to get him. Why is the killer in chief off-limits if a 19-year-old conscripted into his brutal army has to face the bombs and missiles of March?

Given all this white noise, it’s no surprise that a Gallup poll reported this week that Americans support the military action in Libya by a relatively narrow margin of 47 percent to 37 percent. But curiously, the interventions that have commanded that lesser level of support — in Grenada, in Haiti, in Kosovo and the Balkans — have been far more successful than Iraq and Afghanistan, which registered approval levels between 76 and 90 percent.

In the end, the nitpicking and point scoring of the moment won’t matter. The stakes are high, and Obama has to know it. America will be strengthened, and so will he, if the enterprise succeeds — and he will be blamed if the mission isn’t actually accomplished. For the president and for the country, as well as for the people of Libya, there is no substitute for regime change there. Otherwise, we will face a higher likelihood of regime change here.