In order to say the JSA should be more like the military, they should first start reconsider the candidates they let in. Superheroing, especially in teams, is based on the concept of "we the group need this person" or "this person, with their skills and maturity, has reached the stage where they can be useful/deserve to be a part of the group". Superheroing is by definition for people out of the norm. The military is the exact reverse, it's about any citizen physically fit for it having the right or the duty to serve and defend their country.