That's why norms exist. Most previous presidents never would have had this problem in the first place because they would never suggest using US troops on citize

That's why norms exist. Most previous presidents never would have had this problem in the first place because they would never suggest using US troops on citizens in the first place. If they needed to do something that even approached violating a norm, then they would go out of their way to affirm that they still supported the norm and to explain their actions. Obama was given more benefit of the doubt partially because he mostly followed norms. By going out of his way to flout norms, Trump has brought this sort of mistrust and criticism on himself. Therefore, it's not really reasonable for his supporters to complain about it, it's exactly what they signed up for. Remember that Republicans style themselves as the party of personal responsibility.