Joining the military means exposing yourself to the horrors of war; being shot at, civilian casualties, watching people die in front of you, etc. It's impossible for the average person to go through something as traumatic as war and not be psychologically affected. And if you go through all that when you're only 18, it has to be worse.
At 18, you are technically considered an adult. Even before this, most are perfectly capable of making reasonable decisions for themselves. The army fully pays for your college and it also provides good experience. There are also many divisions of the army, including medical and law that could give a background for future professions
Trust me, I live in a small army town, and I know plenty of kids in my high school who are joining the military one they leave high school.
What a lot of people, like @ladiesman, fail to understand is that not every kid can afford to go to college, and not every kid wants to. So, after high school, what are they going to do until they're old enough to serve, just sit in their parent's basements and eat Cheetos?
I hate to say it, but for most kids, it's either join the army, or do nothing, there is no middle ground in some cases.
The armed forces is not all men going to the front lines and shooting at people. There are a lot more options such as mechanics, intelligence officers, engineers etc. The military can support people economically, provide education and give them life experience while also giving them all the skills they need to live in life (money managing, insurance help). Kids can gain a lot more from the military than just 'shoot to kill'.
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