The US is a superpower, and uses the military to create mostly stable political structures around the world that benefit the US. The oceans are patrolled around

The US is a superpower, and uses the military to create mostly stable political structures around the world that benefit the US. The oceans are patrolled around the world, and the nuclear arsenals facilitate mutual assured destruction, which is the only stable nuclear outcome in a world with enough nukes to destroy the planet. This military is an all-volunteer force. This wasn't always the case, but we found out in the 70's that requiring people to join can get extremely contentious if the reasoning for a conflict isn't absolutely clear to the layman. This means there has to be massive recruitment drives to get the people required for the large military. Early recruitment ensures indoctrination, which isn't evil, it just means instilling certain norms and cultures into someone so that they can cooporate and do their job in an environment that humans didn't evolve in.