If this is true, this is sheer incompetence, and it does not necessarily rule out collusion - how on earth were airstrikes approved on coordinates for a Pakistani base, coordinates that had been specifically provided to ISAF to prevent just that?
Two things AM,
First - It is just a part of a news piece, quoting an anonymous source (which is why I colored that part in red), and not the conclusion of investigation.
Second - The same news piece contains another part, which you should also consider with same zeal, that the patrol checked with the Pakistanis before returning the fire - If the coordinates were given, as you claim, and the patrol did check with the Pakistani counterparts, as the anonymous source claims, then it seems the the airstrike was ultimately approved by none other than Pakistani forces, right?
You need not be so aggressive AM, no one is calling NATO an angel, and Pakistanis a devil. If it is not a mistaken identity case, then there has to be a motive behind this airstrike. Let us hear their side of the story too. Conducting such an operation on purpose would be a lose-lose situation to both the parties.
The case might be of incompetence at worst, mistaken identity at best, but not of collusion - that is out of scope because that will make this terrible act a deliberate one. Why would the US deliberately jeopardize its relations with Pakistan, that too at this crucial juncture?
And there are so many other ways to jeopardize the relationship rather than take the blame of killing sleeping ground troops. I wonder if the pilot knew beforehand that the Pakistanis did not have SAMs, because had they had SAMs, then it would have been a suicide mission for the chopper troops. Ah well, a lot of things are still unanswered, let us not give too much credence to anonymous sources and save our breath till the report is out.
I posted that news piece just to open doors to newer angles.