Kabul, Afghanistan ? Gen. John Allen insists that there is “no daylight” between him and President Obama about policy for continued troop withdrawals from Afghanistan next year. That may be technically true, but a political battle is brewing over the future pace of the U.S. military drawdown here.

Allen, the commander of U.S. forces in Afghanistan, says the White House hasn’t given him any timetable for further cuts after September 2012. That’s when the last of the 30,000 “surge” troops Obama dispatched will be gone, leaving about 68,000 U.S. soldiers.

“No one has conveyed to me that at the end of September I’m going to get a number” for more withdrawals through 2013, Allen said in an interview here Tuesday. He said the president’s policy, as he understands it, is for a “strategy-based drawdown” that’s driven by the situation on the ground, rather than a preordained timeline.

Yes, but that’s precisely what the debate is about.

According to Pentagon officials, Allen favors keeping most of the 68,000 in place until late 2013, so that the U.S. has two “fighting seasons” to bolster Afghan troops before giving them full responsibility in 2014. But Vice President Joe Biden and some other administration officials want a commitment to steady, sustained withdrawals through next year’s election campaign. Allen told me that “there could be a quicker drawdown” if military conditions allow but that there is no “glide path.” Some in the White House would disagree.

Does this sound familiar? It mirrors the wrangle that surrounded Obama’s December 2009 decision to send more troops but start withdrawing them in July 2011 — and the debate this year about how quickly the 30,000 should come home. Obama could make it easy if he just left the decision to his commander. But for Obama on Afghanistan, nothing is easy.

Behind the issue of troop withdrawals are some interesting but little noticed changes Allen has made in Afghanistan strategy since he became commander in July, taking over from Gen. David Petraeus. Basically, Allen wants to accelerate transfer of responsibility to Afghan troops in some key regions — preferring to take these risks sooner, when the U.S. has more troops available for backup, rather than later.

Allen’s adjustments involve the transition schedule: He shortened this process and front-loaded it. In the latest phase, announced last month, he included the once-shaky capitals of Ghazni and Wardak provinces; the next phase, in spring  2012, may include volatile Nuristan and Kunar provinces on the Pakistan border as well as Helmand and Kandahar provinces, two key battlegrounds in the south. By mid-2013, responsibility could be transferred for Paktia, Paktika and Khost provinces, three hotspots on the eastern border known as “P2K.”

“Nobody knows how it will go after Afghan troops take the lead,” explains one U.S. commander. “What you want is enough troops to back the Afghans up credibly, so they don’t lose confidence.” One reason this speedup is possible, he says, is that security has improved this year in southern Afghanistan, where another commander says attacks are down about 8 percent compared to a year earlier. This allows more U.S. forces to move east, where the fight is harder.

At a meeting Wednesday in Kandahar, U.S. officers described what they said was improved security in the southern provinces of Oruzgan, Zabul and Kandahar — and better performance by Afghan troops. Such upbeat reports have sometimes proved premature. But Gen. Ray Odierno, the U.S. Army chief of staff, said after the meeting: “My take-away is that the Afghan army and police are making progress, and in some parts are beginning to take the lead.”

What about the Taliban? They appear to have had a tough 2011, but intelligence reports indicate they are making plans to take control of some provinces after 2014, on the expectation that Afghan forces won’t be strong enough to stop them.

One boon for the Taliban is that governance is very poor in most parts of Afghanistan. That’s the weakest link of the U.S. strategy — and a problem even the optimists don’t contest.

“As Gen. Allen moves forward, he needs flexibility to execute his strategy,” argues Odierno. But it will fall to Obama whether to endorse such a flexible, “strategy-based drawdown,” or opt for a faster timetable — with its political appeal for a war-weary America.

My sense is that Obama should listen to his commander in the field — especially when he seems to be speeding up the process that would allow withdrawal of most U.S. troops by 2014.