U.S. aid to survivors of the catastrophic Indian Ocean tsunami (search), including the largest American military operation in south Asia since the Vietnam War, could help restore some U.S. prestige in the Muslim world that has been lost in Iraq (search).

But U.S. political leaders and analysts caution Americans shouldn't over-trumpet the American role, or risk a backlash.

After a sluggish start, President Bush pushed the U.S. response into high gear, ordering an expanding relief mission -- by land, by sea and by air -- and enlisting both his brother, Florida Gov. Jeb Bush, and his father, former President George H.W. Bush.

"What it does in the Muslim world, the rest of the world is giving an opportunity to see American generosity, American values in action," Secretary of State Colin Powell said Tuesday in Jakata after meeting with Hassan Wirayuda, his Indonesian counterpart.

"America is not an anti-Islamic, anti-Muslim nation," Powell said. "America is a diverse society. We respect all religions."

Jeffrey Bader, a former Asia expert on the National Security Council (search) in the Clinton administration and now an international consultant, said, "This gives us an opportunity to remind the countries in the region that there are things that we can do that no one else can do -- and, in particular, China can't do."

"I thought the first few days were a lost opportunity, but then the administration stepped up to the plate," Bader said.

As the U.S. military delivered tens of thousands of pounds of food and supplies, Bush sent his hurricane-relief-experienced brother with Powell to the region and put his father and former President Clinton in charge of a drive for U.S. private contributions.

"The devastation in the region defies comprehension," the president said Monday, eight days after one of history's greatest disasters claimed up to 150,000 lives in 12 countries and left millions stunned and homeless.

Ship-based helicopters as well as Air Force cargo planes and Navy surveillance aircraft joined the humanitarian relief effort, and thousands of Marines were on the way. The Pentagon also dispatched a 1,000-bed hospital ship from San Diego.

The mission is one the United States is uniquely equipped to carry out, with a military budget that dwarfs all other nations.

Images of U.S. troops delivering supplies and medical help to survivors in wrecked villages was a welcome contrast with months of pictures of fierce fighting, prisoner abuses by U.S. soldiers, suicide bombings and land mine attacks in Iraq.

But while the United States may generate some goodwill among Muslims and blunt Al Qaida (search) recruiting efforts, it will be squandered "if the purpose of this is seen as political rather than humanitarian," Bader said.

Indonesia (search), which suffered the largest loss of life in the tragedy, has the largest Muslim population in the world. The Bush administration hopes to bring it and other afflicted nations more directly into its War on Terror (search).

Powell called it "an investment in national security."

Still, he told reporters, "We are not doing this because we are seeking political advantage or just because we are trying to make ourselves look better with the Muslims. We are doing this because these are human beings in desperate need, and the United States has always been a generous, compassionate country."

Michael O'Hanlon, a military and foreign policy analyst at the Brookings Institution, said the relief and reconstruction effort should bring "some slight benefit" in terms of improving the U.S. image. "It always is nice to be able to help people.

"On the other hand, if we push that argument ourselves, that we should be forgiven for past sins or perceived sins because now we are helping out, people will think we're being very crass and exploiting a humanitarian tragedy for our own benefit," O'Hanlon said.

The U.S. response "was necessary, and not really debatable," he added.

The Pentagon said the Air Force had delivered 430,000 pounds of supplies as of Monday.

A major part of the relief effort is a collection of 12 ships from the Navy's Military Sealift Command (search), including six laden with equipment and supplies to support 15,000 Marines for 30 days, and also carrying food, fuel, medical supplies, construction equipment and other materials.

Among the Navy warships closest to the area when the tsunami struck on Dec. 26 was the aircraft carrier USS Abraham Lincoln, on a port visit at Hong Kong. Within a few days it was off the coast of Indonesia's Sumatra island, its helicopters delivering food, water and other supplies to survivors.

The elder Bush, making rounds of television interviews with Clinton, said that in many Muslim areas "we are not fondly looked upon today. For the most part, this will elevate the standing of the United States. But that's not why we're doing it."

Added Clinton: "This is one of those things where you just follow the do-right rule and hope it works out."