True. The cops didn't seem worried at all. The group on the landing at the top of the stairs was small. They were not out of control or violent. There were enough cops among them and on the stairs to clear them out if they wanted to, but it appears the cops were not worried and were about to depart when the shot was fired. Clearly the cops in tac gear were not in communication with the security on the other side of the doors.
When dealing with unarmed people, you can't just draw a red line and shoot anyone who crosses it. But it seems like that might be what happened. They were acting like USSS protecting POTUS.
That is exactly what the guy who shot was doing. Those doors were his line and he was going to shoot anyone who crosses it and that’s exactly what he did.. she started to enter and he did not hesitate at all to kill her.