The question is how did it happen? There are a couple possibilities. One, those Pakistani troops were working with the Taliban and were too obvious about shooting at our side. Or, as some NATO officials have suggested, the Taliban engineered the incident by getting between our forces and the Pakistanis, and shooting at us from positions to make it seem like the Pakistanis were shooting.
If I remember correctly, sometimes the North Vietnamese would get between two American units and fire in both directions to get our units shooting at each other.
The second option seems to be the most likely explanation so far, in my opinion. This would reinforce my contention that our alliance with Pakistan is still a net positive. The Taliban may get some help from Pakistan, but their relationship with Pakistan is a net negative and they'd dearly love to break our alliance, in my opinion.
I'll add something else, too, that the Pakistani government should think about. The air strikes took place over two hours. Why wasn't there close enough cooperation to get the strikes stopped? Friendly fire incidents happen in war. Even when an enemy isn't trying to engineer them. Has Pakistan's self-destructive attitude contributed to the death toll of their own soldiers by downgrading contacts with NATO in retaliation for the Osama bin Laden raid or other perceived wrong doing that they've added to their Big Book of Anti-Pakistan Insults and Grievances?
This incident didn't come out of nowhere. The Pakistanis have contributed to the climate that led to it. Perhaps this is a big enough beating with the clue bat to knock some sense into them.
Or maybe they'll just continue to take our money, double deal on the Taliban just enough to make them a net positive ally for us, insanely focus on India as if India wants that cesspool all to themselves, and blame America for their problems.
What will Pakistan choose? I'm almost giddy in my level of anticipation. But hey, this is what foreign policy realism looks like.
UPDATE: Stratfor looks at the incident and environment. This sums it up:
What actually happened early on Nov. 26 is increasingly irrelevant; it is merely a symptom of larger issues that remain unresolved ...
So far, both we and Pakistan believe alliance with the other provides more advantage than disadvantage. Either could change their minds as the situation evolves. Our response is complicated by the fact that as we watch an Islamist, anti-American Iranian regime go nuclear, we could see a nuclear-armed country whose people are rabidly anti-American (did they even listen to the President's Cairo speech reaching out to the Moslem world?) decide that being on our side (however nominally) just isn't worth the risk.