The donation, which comes as troops may miss paychecks amid the government shutdown, will allow soldiers to attend the association's annual conference.
Trump's partisan comments received cheers or jeers from the crowd, an expression of political views in uniform that would typically result in a reprimand.
The Friday night discussion on veterans issues is part of a series of events from Democrats scheduled around the controversial Army parade in Washington.
Decades after Staff Sgt. William Owens' heroic actions at La Fiere Bridge, his Bronze Star was posthumously upgraded thanks to the efforts of a veteran.