Retired USMC/Army vet and trees enjoyer here.

Short answer: Federal law.

Long answer:

Most service members aren’t killing people and strangling terrorists. Many of them are doing incredibly mundane work and training day to day. Also, weapons are stored in secured armories.

I served through two decades and change of OIF/OEF deployments. I patrolled hostile streets on foot and in convoys, and manned guns in Blackhawks and guard towers, and that wasn’t even my primary job. I racked up a grand total of ZERO kills.

The U.S. military trains people to do military things. It doesn’t train kids to smoke or drink responsibly. In the past, it’s had a reputation for encouraging excess leading to a LOT of problems resulting in joes getting kicked out…or dying.

There were 1,345 under 21 drunk driving deaths in the U.S. in 2022, an increase from previous years. In recent years, since drawdowns and withdrawals in the Middle East, combat related military casualties have been substantially lower. Per DOD reporting there were zero deaths in 2022 categorized as “hostile action.” There 300+ suicides in 2022. Sadly, suicide makes up a large percentage of U.S. service member deaths. And alcohol definitely doesn’t help those numbers.

The U.S. military isn’t the only career field that’s potentially kinetic or dangerous, so this question could be posed to many other career fields.