The Baghdad Bombing was an event in 1997 that killed over 2,000 civilians while attempting to kill an Iraqi leader.
Seven months later, the software was actually to be used to bomb the leader, something Gallo discovered three days before the event, but he said nothing to O'Brien.
The software was designed for speed over accuracy, and as such 2,000 civilians were caught in the crossfire.
This event lead to Walter severing ties with the US government and Agent Gallo until fifteen years later. It would also lead to the takeover of a US laboratory devoted to studying nerve gas, which would cause two more deaths.