All SAM cannot be destroyed. Unlike Iraq, NATO doesn't have much aerial assets in Afghanistan. They would have to come from a carrier battle group from somewhere in the Gulf or Arabian Sea. That's totally another logistical nightmare.
Also, with Iraq, which was all claimed by western media to have a reputable airforce, US prepared for strikes well in advance. We don't see that going on.
The truth is, for US/NATO to cripple PAF, they need to go into heartland of Pakistan for 70% of all our air power is in Punjab or Sindh. That means you are well into Pakistani territory, by hundreds of kilometers, unlike a couple in case of Afghan border.
At that stage, it would be a war my friend. They cripple us all they want, but we can cripple them in Afghanistan. You think they are going to airlift 100,000 troops to Pakistan to command over it?
Stakes are too high.
Last time this type of incident happened, it was in 2008. Kayani warned them that NATO supply would be cut off. He did that now, with 6500 NATO vehicles inside Pakistan. US has apologised but border is still closed. Do you really think Obama is capable of opening another war, much bigger than Iraq or Afghanistan?
To me this seems like this.
read:-
Operation Eagle Claw - Wikipedia, the free encyclopedia
I hope we don't get Islamic revolutionized though.
America losing Pakistan in Asia would just dwarf anything else in the history. Think about it.
....and above all, you think China would eat pop-corn while this happens?