The US can and IS doing it. But they are stretched thin. It is easier for us to do this, because unlike the US, we have decades of anti-insurgence experience. Our pilots are adept at bombing mountain sides - how do you think they managed kargil without crossing the LOC?
Besides, we don't have to worry about longer term things like human rights abuses etc. The US is trying to stay put in Afghanistan. Our troops need be there for no more than a year. Moreover, the US is very cautious about conducting any activities near the Pakistan-Afghanistan border. That place is the most lawless area, the biggest bugbear of the Americans, but they don't want to piss off Pakistan, so they are circumspect about it except when they absolutely HAVE to. We on the other hand, are getting absolutely nothing from the Pakistanis of late - just a day ago the mother******* killed 32 Hindus in J&K. We can afford to piss off (an on) General Mush.