In reality he's as weak as they come, hiding behind tweets & not having the courage to stand up to Putin or Kim. Imaging himself as the commander of a militia "army" makes him feel tough. Remember all his comments about "the Generals"? He both idolizes them & feels inferior to them which causes him to put them down in an effort to pull them down to his level.

His comments about militia groups are his attempt to cast himself as "a General."