“He has hurt the military,” said Ms. Fangmann, who lives in Arizona, one of several states in play this November with a high percentage of veterans and active-duty service members. “Bringing in active-duty members to the streets was a test to desensitize people to his future use of the military for his personal benefit. I think the silent majority among us is going to swing away.”…

Some members of the military — who are not permitted to speak about politics publicly — and their families have been posting critically on social media about the president and policies of his that they once supported. Others, who have never been excited about Mr. Trump as their commander in chief, have begun to speak out, join protests and volunteer for progressive causes.

They say that Mr. Trump has politicized the armed forces — which pride themselves as being above politics and discourage partisan discourse in their ranks — and has threatened the Constitution, both of which they deem as last straws.