Not really. Once he turns 18, he's considered an adult and is free to make those decisions.
No, they cannot.
They could go into the army at age 18 at about the time of the civil war
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Joining the military in the US is voluntary. He doesn't have to join if he doesn't want to.
Your question is unclear. If your child is 17 he needs parental permission to join the Army. At 18 he will not need your permission. One thing to consider is whether or not it's worth the drama just to thwart him for a few months. As a parent who was against my son AND daughter joining the US Army in 2002, I was completely wrong. The experience was excellent for both of them. They did a lot of growing up, and it was 100% good.
No, they are not over 18, but even at 18 and over there are going to be people who will hate being called Mr and will ask you to stop it.
When he becomes an adult. That would be 18 years of age.
Yes as long as your son is still a fulltime student in High School until he graduates. If he is not in school then no it will stop. I hope this helps you some.
Technically, the age of joining was 18 but many went younger.
See Link BelowChild Support Age-At what age does child support stop and what steps need to be taken to bring this about?
Not much really you just had to go to an office with commanding soldiers in and say you wanted to join up and tell them you were 18 because they were very strict about under 18's joining
Getting into the military without a diploma depends on which branch your son is interested in. For instance, the Navy he could not, but the Army he could join without a diploma.