US troops made a big mistake. Now, they have to make up for it.
I am no fan of conspiracy theories, in fact I despise any such thought.
However, whichever way one thinks about it, this story is quite unbelievable. If it was in someone's interest to kill Sgrena, then this is a failure. If it was in someone's interest to protect prisoners, then this is a failure. The truth probably lies somewhere between these two extremes: the italian secret service did not signal its position to american troops in a very accurate way. But, then US troops made a fatal error.