With Desert Storm, you were dealing with flat desert, an utter and complete moron and military commander, a bunch of yes men, who had to go along with him (or they and their entire families would have been strung up with piano wire), a fourth rate army with horrible morale, and armaments in a dilapatated state, and a communications infrastructure that the U.S was familiar with because they and their allies sold them most of the equipment, and, they had intelligence help from Russia and the rest of the alliance.

Afghanistan is different, and more closely comparable to fighting the North Vietnamese, and you won't have entire divisions surrendering to the attackers en masse. They'll fight to the death of every last man, woman and child who can throw a stone, molotav cocktail or fire a gun. And Iraq and Iran will get drawn into it, and who the hell knows, maybe even China.

Damned if we do anything and equally damned if we don't.