If Trump had not responded to the Melania tweet, what would he have lost? If he ignored Megyn Kelly, just refused to go on her show, what would he lose? one does not need to scream at the top of ones lungs to be heard and to be effective. one does not need to act like a 12 yo on twitter to fight back effectively. I am sick to death of people just excusing every single thing he does, when much of it is indefensible. Trump supporters would have far more credibility if they acknowledged when he is acting like a jack@$$, rather than just lockstep applauding everything he does.
If you don’t stop the first punch you can be assured that a second one is coming. There is no other response then to fight your enemy on their terms not some made up PC theory.