Wielding a few hundred elite troops and thousands of precision-guided missiles, the United States has spearheaded the defeat of Taliban and terrorist forces in Afghanistan while waging perhaps its most finely tuned war ever.
The almost surgical application of US force has so far helped limit American casualties to a handful of troops - none of them killed in enemy combat - while also minimizing the deaths of Afghan civilians.
All indications are that the Pentagon hopes to use the same finely calibrated investment of force - coupled with $25-million rewards - to achieve its ultimate goal in Afghanistan of rooting out the leaders of the Taliban and the Al Qaeda network of Osama bin Laden.
"It's sort of the immaculate approach to warfare," says Mackubin Owens, a professor of strategy at the Naval War College in Newport, R.I. While the Pentagon stresses that the US cannot fight an antiseptic war, so far the Afghanistan campaign has followed the past decade's pattern of use of heavy airpower and minimal US casualties.
The Pentagon's overall approach, a marriage of least-risk military strategy and political expediency, has its drawbacks, however. Chief among them: By relying primarily on Afghan opposition forces for manpower, the United States cannot dictate the outcome when its interests and those of the opposition diverge.
The limits of US influence are evident, for instance, in the occupation of Kabul by Northern Alliance resistance forces, which took the city against Washington's will. US defense officials also acknowledge their limits in negotiations between opposition leaders and Taliban-Al Qaeda holdouts in Kunduz and Kandahar.
The Pentagon says it opposes - but cannot prevent - deals for the escape of Taliban leader Mullah Mohammed Omar from Kandahar or the release from Kunduz of non-Afghan Al Qaeda fighters, who officials warn could "destabilize" other countries and should instead be imprisoned or killed.
"We are able to provide input into that process, but we're not in a position of determining it or controlling it," Defense Secretary Donald Rumsfeld said Monday.
In the long run, experts say, America's calibrated approach to the conflict may also limit the US role in the delicate process of shaping a broad-based, multi-ethnic government that could prevent Afghanistan from again becoming a base for terrorism.
"It brings you to an age-old question about these kinds of wars, small wars for major powers. The major power wants to limit its investment ... yet too often the small investment is too little to produce the significant result that is desired," says Air Force Col. David Tretler, a professor of strategy at the National War College.
Nevertheless, the Pentagon remains guardedly optimistic that its current formula - precision bombing, US Special Operations Forces, and cash rewards - will be enough to eliminate the Taliban and Al Qaeda in Afghanistan without reverting to the risky and cumbersome deployment of large numbers of US ground troops, an option that Washington has never ruled out.
Unprecedented precision and potency in the use of US air power in Afghanistan have been crucial elements in the success of the campaign so far, experts and officials say. Pentagon officials say the US airstrikes in Afghanistan have been even more precise than those in 1999 in Kosovo, where 90 percent of the US munitions fired were precision-guided, compared with only 10 percent during the 1991 Gulf War.
Several factors - including the lack of "high value" Taliban and Al Qaeda targets, their location close to population centers, and the desire to avoid causing civilian casualties that could inflame Muslim public opinion - added up to a more finely tuned targeting process than in Kosovo, says Pentagon spokesman Lt. Col. David Lapan.
Indeed, the complex calculations involved in pursuing key targets while avoiding civilian deaths have in some cases delayed the permission to strike, Secretary Rumsfeld says, and, according to news reports, caused some grumbling among US military commanders. "What do you gain by hitting that location if in the process you're going to blow up three hospitals and four orphanages and three schools to get four people?" Rumsfeld said.
Despite such care, errant missiles have caused some civilian casualties. Ultimately, it was high-flying, stealthy US warplanes, honing in on targets with the aid of laser guides, that weakened and cracked the Taliban's militia, which had little means for fighting back, experts say.
A second decisive factor has been the use of Army Green Berets and other elite, highly trained US commandos, who now number several hundred in Afghanistan. Primarily deployed to identify targets for aircraft and to help supply and direct opposition fighters, these commandos have language skills and are trained in "unconventional warfare" - dramatically illustrated when some rode horseback into battle last month with Northern Alliance fighters.
Today, US "special ops" teams of about a dozen men each are spread out across Afghanistan, gathering intelligence, setting up roadblocks, and watching key travel routes for Taliban and Al Qaeda leaders.
These lightly armed forces, however, are not engaging in a cave-by-cave search for the leaders, a job that would require "different types" of forces, Rumsfeld said.
Money is the Pentagon's third key weapon. On Tuesday, US jets began dropping thousands of leaflets over Afghanistan, offering a $25-million-dollar reward for information leading to the location or capture of Mr. bin Laden or Ayman al-Zawahiri. US aerial broadcasts also urged Afghans to take part in a "cash reward program" for turning in Al Qaeda terrorists.