Ego and Deflection Motivate Trump

Donald Trump's Twitter war with the parents of the Muslim American Soldier killed in Iraq suggests a fragile ego and lack of self control. Alternately, if that doesn't explain Trump's insistence on keeping this story alive, fanning the flames with childish insults, maybe his focus on Kahzir Kahn and his wife is more strategic. 
It certainly could be The Donald's way of deflecting attention from what is arguably the more important recently breaking story -- the billionaire businessman's suspect links with Russia and President Vladimir Putin.
It's likely a little bit of both.