WASHINGTON – More than 100 days after the United States and NATO allies launched what was supposed to be a quick air campaign in Libya, Pentagon officials concede that the effort has little strategic value for the U.S., and the alliance's desired outcome there remains unclear.

Instead, with NATO unable to bring an end to the fighting, the mission has run into stiff opposition from both parties in Congress and led military officials to fret privately that even the limited U.S. role will generate more ill will in the Arab world.

What's become an open-ended conflict, military officers and experts say, illustrates ill-defined U.S. objectives, the limits of relying solely on air power and the lack of diplomatic tools to broker an end to Moammar Gadhafi's regime.

Thousands of anti-Gadhafi rebels have been killed, and some at the Pentagon worry that the mounting deaths and reduced U.S. involvement have jeopardized what President Barack Obama called a campaign to protect Libyan civilians.

"We are losing the good will this was supposed to create," said one senior military officer who wasn't authorized to be quoted by name.

Perhaps undercutting Obama's rationale for war, Defense Secretary Robert Gates, in a series of exit interviews ahead of his retirement, has begun to describe the U.S. involvement as payback to NATO nations – which depend on Libya's oil reserves – for joining American troops in fighting in Afghanistan, which was mainly a war about U.S. strategic interests.

"These allies, particularly the British and the French, and the Italians for that matter, have really been a big help to us in Afghanistan. They consider Libya a vital interest for them. Our alliance with them is a vital interest for us. So as they have helped us in Afghanistan, it seems to me that we are in a position of helping them with respect to Libya," said Gates, who opposed U.S. involvement in Libya from the beginning, last week on the "PBS NewsHour."

On Wednesday, Obama vigorously defended the campaign, saying, "We've protected thousands of people in Libya, we have not seen a single U.S. casualty, there's no risks of additional escalation, the operation is limited in time and scope."

But Obama also said that Gadhafi needs to go and that no political settlement is possible with him in power.

U.S. military officers say that NATO's commitment of military force doesn't match that goal.

The NATO effort is almost exclusively an air campaign, which is designed to ground Gadhafi's planes and strike at his weapons sites.

But at times it appears that NATO has tried to topple Gadhafi, which experts said demands ground forces, a larger air campaign and a clear plan for who will lead Libya in the aftermath of the regime.

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Call Nancy Youssef, McClatchy Washington Bureau, (202) 383-6080.

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