If you want to join the Army

In my country if you want to join the Army. As a rule you have to be 18 years or older. Before this age, you will not be able to form part of it. The reason for this is that people under age are considerate immature. One of the clearest examples is that when you are doing your military service, if you want to get a job as a soldier, and you are under age you will have to wait until you get 18.