(Reuters) - U.S. officials have warned of the potential for catastrophe if Afghan President Hamid Karzai fails to sign a security pact to permit foreign forces to stay in Afghanistanbeyond 2014.
Unless a deal is reached to enable a modest U.S. force of perhaps 8,000 to stay in the country, the Taliban might stage a major comeback, al Qaeda might regain safe havens and Afghan forces might find themselves starved of funding, the officials say. The post-2014 U.S. force envisioned would train and assist Afghan soldiers and go after the most dangerous militants.
But even if the Obama administration abruptly pulls out its entire force of 43,000 a year from now, it would still retain a handful of limited security options in Afghanistan.
While U.S. officials have not discussed a possible post-withdrawal scenario in public, the United States might still, even under those circumstances, continue to provide small-scale support to local forces, mount some special forces missions, and use drones to counter al Qaeda and help keep the Taliban at bay.
A narrowed security mission would in many ways track a decade-long shift in U.S. strategy, away from the counter-insurgency campaigns of the 2000s toward the Obama administration's preference for low-profile support to local forces combined with occasional targeted operations.
Even so, full withdrawal of the main U.S. force would make it more difficult to prevent al Qaeda militants regrouping along the wild Afghanistan-Pakistan border and to stop the Taliban from solidifying control of its southern Afghan heartland.
"We have a lot of capabilities, but without the (Bilateral Security Agreement), we are very limited," a U.S. defense official said on condition of anonymity, referring to the bilateral pact the United States is seeking with Karzai.
For now, U.S. officials remain hopeful - in public at least - that Karzai will drop last-minute demands and sign the pact well before Afghan elections in April. They say they have not begun to plan for a full withdrawal or a possible post-withdrawal mission in earnest.
But General Joseph Dunford, who commands international forces in Afghanistan, told reporters in Kabul recently that, "If there's not an answer in December, I expect that we'll begin to do some more detailed planning about some other eventuality besides the (post-2014) mission."
To understand what options the United States might have in Afghanistan following a full withdrawal, "you can look to places where we are already active countering terrorism, like Iraq, Libya, Somalia," another U.S. defense official said.
TARGETED MISSIONS AND SMALL-SCALE SUPPORT
Even if all foreign troops do withdraw from Afghanistan, the United States might still send small numbers of special forces, such as Green Berets, to do limited, short-term training missions at the request of Afghan officials. They might also launch occasional raids against militants, as they have in Libya or Somalia.
"This is a model that's used around the world," the first defense official said.
In October, U.S. forces seized Abu Anas al-Liby, a suspect in the 1998 bombings of two U.S. embassies, in Tripoli, Libya. It is unclear what sort of authority it received from the Libyan government.
The same weekend, U.S. special forces launched an operation against an al Shabaab militant in Somalia but failed to capture him, U.S. officials said.
In Iraq, following the U.S. military withdrawal in 2011, the United States set up a large security office attached to its embassy in Baghdad to oversee military sales and provide limited support and advising to the Iraqi government.
U.S. special forces have also been invited to return to Iraq to provide counterterrorism and intelligence support to Iraqi forces, the general who headed that office said last year, according to a report in the New York Times.
The U.S. military also is providing some training and equipment to security forces inYemen, defense officials have said, as the Obama administration seeks to weaken al Qaeda and other militants in the Arabian Peninsula.
Robert Grenier, a former director of the Central Intelligence Agency's Counterterrorism Center, said that if withdrawal of the main U.S. force from Afghanistan becomes necessary, the United States should consider putting some special forces under CIA authority to train local forces or perform limited counter-terrorism activities, possibly along with some members of the CIA's small paramilitary force.
"The U.S. footprint would be much smaller, and we would have many fewer capabilities. But it might not be a bad thing," Grenier said. A light U.S. footprint would give Afghan forces more of a leadership role in pursuing militants than they have had in the past, he said.
Retaining even a very narrow ability to support elite Afghan soldiers could be especially important if plans for a larger training mission collapse along with U.S. efforts to finalize the security pact. Top U.S. officials have warned that the $4 billion a year in outside aid promised for Afghan forces would be less likely to materialize if the full departure of foreign troops limits lawmakers' ability to track U.S. aid.
The administration would also have to rethink much of its development aid as well as its diplomatic strategy if U.S. troops depart.
Without outside help, Afghanistan's central government will likely lack the means to pay police and soldiers, encouraging a fracturing of its military along ethnic or regional lines.
"The biggest risk if we go to the zero option is that the Afghan military falls apart, and then the Afghan state falls apart," said retired Lieutenant General David Barno, who commanded U.S. and NATO forces in Afghanistan from 2003-2005.
The United States would likely seek approval from future Afghan leaders for most or all of post-withdrawal training activities and counter-terrorism activities - possibly including the use of drones, which have been a defining feature of the Obama administration security strategy in far-flung places.
President Barack Obama said in May that he hoped progress against al Qaeda and other militants would "reduce the need for unmanned strikes" in the Afghan war theater by next year.
However, the lack of a sizeable U.S. troop presence in Afghanistan could mean that drones become one of the few remaining tools the United States has against militant groups in the region.
Micah Zenko, a fellow at the Council on Foreign Relations think tank, said it would be very difficult to continue the drone program if Karzai's successors decide against allowing launches from Afghan soil after foreign troops withdraw.
Central Asian nations that might allow such flights are too distant from likely target areas, while the U.S. military currently has only limited ability to operate drones from ships in the Arabian Sea or elsewhere.
"Short of receiving basing access from a neighboring state, and overt overflight support from Afghanistan and Pakistan, it would be a very difficult operational risk to conduct drone strikes into Afghanistan or Pakistan," Zenko said.
In 2011, Pakistan's then-defense minister, Chaudhry Ahmed Mukhtar, said his government had asked the United States to vacate an air base in southwest Pakistan he said was used to launch U.S. drone flights.
Grenier said Pakistan might be willing to allow future drone launches, provided it was given substantial control over drone activities and targets.
"Under those circumstances, the politics surrounding Pakistani sovereignty might not be a big issue," he said.
(Additonal reporting by Phil Stewart and Matt Spetalnick; Editing by Alistair Bell and David Brunnstrom)