I was a cop for over 30 years so I understand more about the use of deadly force than you ever will.
I've known a lot of agents from the BATF as well as from the FBI, Secret Service, DEA and INS.
I know the training they receive and I don't for one instant believe the feds shot first.
The Branch Davidians on the other hand were a bunch of gun-happy head cases.
The feds blungled to whole incident badly, but it was because of the turf wars the BATF brass was engaging in with other federal agencies, not because the field agents were out of control.