Former CIA man Bruce Riedel, who chaired Obama's (first) Afghanistan strategy review earlier this year, writing with co-author Michael O'Hanlon, warns against what you might call the Biden strategy:

The fundamental reason that a counterterrorism-focused strategy fails is that it cannot generate good intelligence. Al-Qaeda and the Taliban know not to use their cellphones and satellite phones today, so our spy satellites are of little use in finding extremists. We need information from unmanned low-altitude aircraft and, even more, from people on the ground who speak the language and know the comings and goings of locals. But our Afghan friends who might be inclined to help us with such information would be intimidated by insurgent and terrorist forces into silence — or killed if they cooperated — because we would lack the ability to protect them under a counterterrorism approach....

The second reason a counterterrorism-oriented strategy would fail is that, if we tried it, we would likely lose our ability to operate unmanned aircraft where the Taliban and al-Qaeda prefer to hide. Why? If we pulled out, the Afghan government would likely collapse. The secure bases near the mountains of the Afghan-Pakistan border, and thus our ability to operate aircraft from them, would be lost. Our ability to go after Afghan resistance fighters would deteriorate. And the recent momentum we have established in going after Pakistani extremists would be lost.