Having never been in the armed forces myself, I don’t know what kind of culture it promotes first hand, but I think it’s very important for the people of a country to have a commonly shared experience. Bringing people together from all walks of life, treating them in the same way, giving them life skills and training, and pushing them to compete and excel, I think it would do wonders for the world.
And, yes, pulling kids away from digital distractions, that would be an improvement too.
You say it well, people working towards a common goal promotes teamwork and collaboration and the world needs more of it.