We were under attack.
The president was in a known location.
300 children and civilians were present.
Seven minutes is plenty of time to die and take them with you.
His number one concern at the time was supposed to be to remain safe and get to a secure location. This is bottom line in any crisis situation. You protect the commander in chief so that he can lead.
His secondary concern should have been the children who he was putting in danger. He had no way of knowing what form these attacks were or could take and should have removed himself immediately.
If the terrorists has targetted him personally and he had stayed and those children died because he sat on his ass would you want to fact thier parents and tell them "Well, he's just this guy like the rest of us. It's OK."
It was a dereliction of duty and a major dropping of the ball.