I plum missed this, sorry.
My impression of the situtation in Pakistan would be to say that no, it’s not the case. Pakistan does not appear to be actively cooperating with al-Qaida terrorists, and in fact seems to be making an effort to fight them. There’s no reason to attack PAKISTAN. Even if there was an imminent threat somewhat in Pakistan that absolutely had to be bombed right away - they detected bin Laden riding atop a newly stolen A-bomb like Slim Pickens - then the appropriate course of action is a limited strike, not some general invasion of Pakistan. The government of Pakistan does control the great majority of the country. The appropriate thing to do here is to help Pakistan fight them, it seems to me.
If Pakistan was offering aid and comfort for the terrorists, or if the Pakistani government collapsed and could do nothing, then military action could be justified (assuming that in fact there is a threat to the USA there. I don’t know if that is the case. Do we know bin Laden is there??)