Ever since Philippine independence from the US in 1946, the place of American forces in this former colony has remained contentious.
So the uproar dominating discussion among the Filipino elite over the role of American forces in the south, where they are helping eradicate an ally of Al Qaeda, is nothing new.
As usual, the population as a whole overwhelmingly supports US action. But read the press here, and you would think Uncle Sam had invaded the country.
What is new is that, for the first time since World War II, US forces may engage in hand-to-hand combat alongside Filipino forces. Some 600 highly armed US troops are either en route or already in action in Mindanao, "advising" and "training" Filipino forces. The Abu Sayyaf group has acted with impunity in this southern province for several years, with substantial backing from Osama bin Laden.
For President Gloria Macapagal Arroyo, mopping up Abu Sayyaf could help bring back foreign investors and tourists, and get the economy moving again. For Washington, a quick win would maintain momentum after defeating the Taliban.
But the sensitivity of American-Filipino relations always intrudes. When Kansas Sen. Sam Brownback (R) said the Philippines was going to be the "next Afghanistan," half the Filipino Senate and press went ballistic.
Of course Senator Brownback didn't mean that the Philippines would be "targeted" as Taliban Afghanistan was, with the whole country under bombardment; Abu Sayyaf operates in a small portion of the country. But undoubtedly Brownback's knowledge of Filipino geography was scanty. US-Filipino relations have long been bedeviled precisely by such misunderstandings. This one threatens the mission.
The Filipino Constitution forbids the stationing or role of foreign (read American) troops. The presidential palace insists it has made a simple executive agreement with Washington so that it can get on with their mutual task. The US role is to train and assist, and its need to "defend itself" in the process explains the high firepower it brings along. So the Filipino government's argument goes.
The polls are supportive because Filipinos are tired of being pushed around by the small southern guerrilla bands. Worse, tourism - indeed, the whole program of attracting foreign investment - has been set back at least a year by the kidnappings and ambushes that have become footprints of Abu Sayyaf.
But powerful nationalist forces are swinging into action. The Filipino defense secretary has turned the country into "an extension of Fort Bragg," Rafael Mariano, the head of a radical group, said. "These Yankees must go home." The old alliance that helped drive US bases out 10 years ago is out in force. Investigations of the legality of the American role are everywhere demanded.
President Macapagal, a talented economist and daughter of the Filipino president who inaugurated a third world-oriented foreign policy, is no American patsy. But she has a dilemma. To revive the economy, she must end the rebellion in the south. The Americans are only too willing to help. She has been forthright all along in announcing the US role, and tirelessly repeats that Filipinos will do the fighting.
But local suspicions that the US role has become something beyond a training exercise are well founded. The leading commentator here, Amando Doronila, put it plainly: If the Philippines needs the American troops so badly - and it does - isn't Filipino sovereignty in question?
The only reasonable answer is the one believed by the majority supporting the US role, namely that the more questionable course would be to allow terrorists to run the Muslim south and scare off remaining investment. The beleaguered president is hoping for a swift victory against the terrorists, before too many investigations bring to a halt what looks like a winning coalition of Filipino and American forces. If the combat drags out, opposition elements could embarrass Ms. Macapagal and force the reduction of the American role.
There is little reason to doubt that her gamble will pay off. Filipino forces are hankering for a fight, and with well-armed Yankees at their side in offensive combat, they are unlikely to stop until complete victory. Nobody in Manila is going to stop them while they are winning.
W. Scott Thompson is adjunct professor at Tufts University's Fletcher School of Law and Diplomacy at the Asian Institute of Management.