What are we doing?

The Times reports on blatant fraud in the Afghan election--a district where no one voted, but almost 24,000 votes were delivered (literally) for Hamid Karzai. CBS says that the Taliban is taking a significant part of American reconstruction aid, through an office that they run in Kabul itself.

So, why are we in Afghanistan? Allegedly, to prevent the Taliban, who pose no threat to the US and have never posed a threat to the US, from taking over the country. Because the Taliban are allies and protectors of al Qaeda. But with Somalia still lacking any semblance of government, and Yemen in danger of falling apart completely, and Pakistan sheltering the terrorist network's leadership, how important is Afghanistan? More to the point, how much longer can we ask our servicemen and women to risk death and disfigurement on behalf of a regime that can't or won't see beyond the hand held out for a bribe?

Why not maintain just enough troops and planes in Afghanistan to keep the Taliban from a complete victory while we wait to see if the Afghans can build some semblance of a state?