Pakistan's nuclear assets are distributed across much of the country, that's the 36th largest landmass in the world. Although I am confident that CIA doesn't have a clue where they are, but I'll suggest for argument sakes that 2 locations are neutralized and the US decides to nab them. Here's what will happen, IMHO:
1) They won't attack, the Americans are smarter than that.
2) They have a fit of fanaticism and send in those stealth helos to take the nukes.
Now let's build on scenario two, at location X. Three choppers are dispatched for location X (Any more and they risk forming a cluster that may result in small radar reflection from each helo, resulting in a significant ping back). From the size of the wreckage, I estimate that helo carries less than 10 people including two pilots. So let's say there are 6 armed SEALS in each. The Helicopters enter Pakistani airspace undetected. They reach site X and:
1) Are spotted, taken alive/killed in cross fire.
2) Manage to infiltrate the facility
Building on scenario 2, now that they are inside the facility, they face hundreds of well trained, fiercely motivated members of the SPD who are also armed to the teeth.
1) They are killed/taken alive.
2) They go Rambo and kill every SPD personnel onsite.
Building on scenario 2, they find the warheads (Under 10) but what do they remove them with? They can't just carry them, time is of the essence as back up is probably inbound.
1) They leave without the warheads.
2) They destroy the warheads on site.
Building on scenario 2, if they destroy the nukes on site, a massive radiation leak will affect much of Pakistan's civilian populace. Depending on the time of year, winds from the bay of Bengal or from the Mediterranean sea will carry the winds loaded with radiation to neighbouring countries. With so much enriched uranium, I predict a Radiation cloud that will put Chernobyl to shame. The Americans are smarter than that.
Conclusions:
1) Any such raid is impossible.
2) Indians go home sad.