Barack Obama beat Sen. John McCain in 2008 to win the presidency. But Obama also ran against President George W. Bush, particularly in appealing to those who thought Bush acted unilaterally in starting the war in Iraq.

So it's especially disappointing -- and wrong -- that Obama has not sought congressional approval for the air war in Libya.

The War Powers Resolution calls for a president to deliver a formal report within 48 hours of the beginning of armed conflict and to withdraw forces within 60 days if Congress has not specifically authorized U.S. involvement. The resolution grants 30 more days for an effective withdrawal. The 90-day period ended on Sunday.

The New York Times reported on Saturday that Obama overruled top Pentagon and Justice Department attorneys on whether the Libyan conflict should invoke the War Powers Resolution. Obama reportedly believes that U.S. military activities fell short of the threshold of "hostilities."

The United States is part of a NATO effort, backed by a United Nations Security Council resolution, to "prevent a humanitarian catastrophe and address the threat posed to international peace and security by the crisis in Libya," according to the White House.

After initial airstrikes, our forces are supporting intelligence and refueling efforts for sorties that have killed Libyans. Most killed have been forces loyal to Libyan leader Moammar Gadhafi. But some have been civilians, like the nine who were hit by a an errant NATO missile last weekend.

These are clearly hostilities -- even if the U.S. military is no longer the lead force doing the fighting.

Robert Gates, defense secretary under both Bush and Obama, didn't use that language Sunday, and instead referred to our involvement as a "limited kinetic operation." But then he implicitly admitted the United States was at war when he said, "Frankly, I think cutting off funding in the middle of a military operation when we have people engaged is always a mistake."

Gates is right on congressional appropriations, if not appropriate language, regarding the war in Libya. Congress should not cut off funding in the middle of armed conflict. Doing so would only embolden Gadhafi, weaken the resolve of the Libyans we're trying to protect, and send the wrong signal to our NATO and Arab allies.

But the administration can't have it both ways. If it needs the money to fight a war, it should say so -- with specific language. What else can a mission that started as civilian protection, but has now crept toward regime change, be called?

Congress has a constitutional and historical role in military matters. Presidents should not be able to have a unilateral and unlimited ability to wage war. If Obama fears he does not have the support for approval, he should more aggressively make his case -- both to Congress and the American people.

To date, ironically, it's the man he beat who's making the most compelling case for the war.

The War Powers Resolution was passed in 1973, toward the end of the Vietnam War. One of the lessons supposedly learned from Vietnam was never to commit troops without the support of the American people.

Their elected representatives deserve a say, and Obama should act accordingly.

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