Restraint would be finding out that your actions will kill people long before 10 minutes prior to the attack. I can't say he has a conscience, but I think someone told him that he might get some bad PR...even from Fox.
Why not watch some documentaries on how JFK behaved when the US faced an international crisis. He didn't strut around like some BSD "talking tough". He listened to advisors...he listened to generals...then he made his moves. Trump struts in...talks tough...and then relies on the opinion on the last person to talk to him. This time the last person obviously wasn't Mr. Mustache.