People who voluntarily join the armed forces are mixed bag, but do not act like those who fought in WW2 and Vietnam were all saints. There were plenty who joined to kill the enemies of the US, remember all of the racially charged propaganda around at the time especially against the Japanese.
Not to say that that was by any means the majority, and contrary to your belief those who have fought in the middle east didn't go there to kill brown people or play xbox. Many joined because they thought what they were doing was right, they were killing those who killed Americans. Then they were killing those who oppressed and gassed their own people.
It is easy to sit on the high horse and disregard them all as racists, which is funny considering just how many "brown people" are members of the armed forces. Plenty of people of Latino heritage, African Americans, Asian, and Arab heritage are soldiers. And it's quite funny that you say they want to "kill brown people" implying that the men and women in the military today are somehow more racist than those soldiers in WW2.
Nobody wants expects you to suck your dick out of basic training, if anything when soliders come out of basic training they are more respectful and disciplined than they are by the end of their career. Because they just had those principles drilled into them.
Your entire post seems to indicate that you have actually little to no contact with the men and women in armed forces and are projecting stereotypes based upon what your political leanings are.
Not to mention, that many do not even join out of a desire but desperation because trade deals and our countries straight out abuse of the central states that they join out of desperation for a future. Most of the areas they live in are drug ridden, with little to no careers that lead to anything other than minimum wage.
We can say that the military actions in the middle east were unjust, but your painting of the actual soldiers as cowards or racist murderers is purely out of ignorance. You are the same kind of person that spits on Vietnam vets coming home with PTSD and missing limbs.
I doubt you have met those types of soldiers that match the cartoonish stereotypes to a T, I doubt you have interacted with soldiers in your life at all. When your argument relies on depicting you are talking about, in the most broad and caricatured way it is doubtful there is much of substance to your account.