I have no idea what really happened but ignorance won't stop me now!
1) Like all accidents, this probably had several things happen at the same time. The Italians panicked when our vehicle showed up. Maybe they thought it was terrorists attacking.
2) Our guys are pumped up because of all the VBIED attacks (I would be). They see a car that won't stop, so they stop it.
3) The cellphone nonsense may be related to jamming. I've read that we jam cell frequencies near our patrols to prevent remotely detonated IEDs.
I totally agree with the other posters. If we *wanted* to kill the woman, she would be in a body bag. Any claims otherwise are [how do Italians write b*llshit?].
About the cell-phones, you are correct, it is becoming standard procedure to prevent anyone from using cell-phones around U.S. convoys. In this case they apparently asked Italian agents to turn them off even as they were talking directly to Berlusconi, which tells me that the soldiers were just following standard operating procedure.