It is too expensive to be the world policeman. Learn from the Soviet Union on Afghan and French on Vietnam. If we do not learn from history, we will repeat them.
If we sent the children of our leaders to the front line, I bet we do not have even one war.
It is unfair to send young kids who do not really understand all the global issues and most likely they could not spell the country's name they are sent to. They should enjoy the best time in their life either in college or new jobs. The college graduates should have a good job instead of waiting tables for years.
Killing is not glorious.
Forcing others to accept our democracy is plain stupid.
Protecting our interest is our excuse (how many oil we save in the current two wars).
Boosting our 'prestige' by killing is no difference from Hitler or the imperial Japanese emperor in WW2.