Trump "fights back." That's one of the defining features of his. When he makes a mistake or whenever someone opposes him in any way, he has to fight back. He can't admit being wrong, he can't admit a defeat. This gets him into stupid fights and escalates things (remember the kerfluffle over the crowd size in his inaugural? A lot of energy was spent on arguing that and even later on he has gone on to argue about every crowd in his rallies and making fun of other people's rallies even if he has to fake evidence to support his claims.)