WASHINGTON - The widening war in Mali has opened divisions between the White House and the Pentagon over the danger posed by a mix of Islamist militant groups, some with murky ties to al-Qaida, that are creating havoc in West Africa.
Although no one is suggesting that the groups pose an imminent threat to the United States, the French military intervention in Mali and a terrorist attack against an international gas complex in neighboring Algeria have prompted sharp Obama administration debate over whether the militants present enough of a risk to U.S. allies or interests to warrant a military response.
Some top Pentagon officials and military officers warn that without more aggressive U.S. action, Mali could become a haven for extremists, akin to Afghanistan before the terrorist attacks of Sept. 11, 2001.
Militants in Mali, "if left unaddressed ... will obtain capability to match their intent - that being to extend their reach and control and to attack American interests," Army Gen. Carter Ham, head of the U.S. Africa Command, said in an interview.
But many of Obama's top aides say it is unclear whether the Mali insurgents, who include members of the group al-Qaida in the Islamic Maghreb, or AQIM, threaten the U.S.
Those aides also worry about being drawn into a messy and possibly long-running conflict against an elusive enemy in Mali, a vast, landlocked country abutting the Sahara desert, just as U.S. forces are withdrawing from in Afghanistan.
"No one here is questioning the threat that AQIM poses regionally," said an administration official who spoke on condition of anonymity when discussing internal deliberations. "The question we all need to ask is: What threat do they pose to the U.S. homeland? The answer so far has been none."
Another U.S. official, who is regularly briefed on such intelligence, said the groups' goals were often hard to distinguish.
"AQIM and its allies have opportunistic criminals and smugglers in their midst, but they also have some die-hard terrorists with more grandiose visions," the official said. "In some cases, the roles may overlap."
The internal debate is one reason for a delay in U.S. support for the French, who airlifted hundreds of troops into Mali last weekend and launched airstrikes in an effort to halt the militants from pushing out of their northern stronghold toward Bamako, the Malian capital.
The Pentagon is planning to begin ferrying additional French troops and equipment to Mali in coming days aboard U.S. Air Force C-17 cargo jets, according to Air Force Maj. Robert Firman, a Pentagon spokesman.
Military planners are still studying the airport runways in Bamako to determine whether they can handle the huge C-17s. If not, they will land outside Mali, and the French troops will be flown into Mali on smaller aircraft. French officials have asked the U.S. to transport an armored infantry battalion of 500 to 600 soldiers, plus vehicles and other equipment.
The U.S. is also providing France with surveillance and other intelligence on the militants.
But the administration has so far balked at a French request for tanker aircraft to provide in-air refueling of French fighter jets because the White House does not yet want to get directly involved in supporting French combat operations, officials said.
U.S. officials have ruled out putting troops on the ground, except in small numbers and only to support the French.
"I think the U.S. ambivalence about moving into Mali is very understandable," said Richard Barrett, a former British diplomat who serves as United Nations counter-terrorism coordinator. Noting the instances where U.S. forces have been drawn into conflict with Islamic militants, he added: "Why would they want another one, for God's sake? It's such a difficult area to operate in."
After 2001, Washington tried to tamp down Islamic extremism in Mali under a counter-terrorism initiative that combined anti-poverty programs with training for the military. The U.S. aid was halted, however, when military officers overthrew the government last March in a violent coup.
Ham has warned for months that AQIM was growing stronger and intended to carry out attacks in the region and internationally. To combat the threat, some officers favor building closer ties with governments in the region and boosting intelligence-gathering and special operations.
But other administration officials question the need for a bigger U.S. effort.
Johnnie Carson, who heads the Africa bureau at the State Department, told Congress in June that AQIM "has not demonstrated the capability to threaten U.S. interests outside of West or North Africa, and it has not threatened to attack the U.S. homeland."
The September attack on the U.S. mission in Benghazi, Libya, has provided fodder for both sides: AQIM members participated, U.S. intelligence officials have said, but the U.S. has found no evidence the attack was ordered or planned by AQIM.
A rebellion last year by ethnic Tuaregs in northern Mali paved the way for AQIM and allied groups, including the Movement for Unity and Jihad in West Africa, known by its French acronym MUJAO, to seize Mali's northern half.
U.S. officials say the Islamist groups have used the Texas-sized area to establish training camps, recruit fighters from African and European nations, including France, and strengthen ties with other African extremist groups.
A U.S. intelligence official said the militant groups' "limited people and expertise" require them to focus most of their effort on holding the territory they've seized. But over time, the official said, the groups' growth could threaten other nations in the region.
"They have to train these guys, provide these guys with skills," the official said, referring to foreign recruits. "At some point down the road, they will probably go back home, and that increases the threat in those home countries."
The militant groups "all appear to me to be essentially criminal networks based on kidnapping and smuggling ... having little to do with Islam or with the remnants of al-Qaida in Pakistan and Afghanistan," said John Campbell, a former U.S. ambassador to Nigeria now at the Council on Foreign Relations.
French officials have depicted their intervention as a stop-gap move until an African military force of 3,300 is ready to train the Malian army and help it recapture territory from the rebels. The United Nations endorsed the mission in December, and the first soldiers arrived in Mali this week, but African officials have said it could take several months before the forces are ready to begin operations.