A lot of these are readiness exercises and large unit drills for concept operations. Most are required from Headquarters yearly, others are unit training to prepare for the upcoming yearly conducted readiness exercise. We do them in the Mojave prior to deployment, as a one month refresher.

Some units test new equipment and tactics, so it really depends on the unit, and what it is doing. Every unit in the military has a specialized purpose. For example your not going to send a communications guy out on a combat patrol as the gunner, or combat arms guy to the radio room to encrypt the radios.

As for units, they wouldn't be using truck drivers to stage an air assault when the Cavalry RSTA units are trained to.

Hope that was simple enough to understand.

Basically, see if the unit can be identified and you will have your answer as to what they are doing.

For all we know they are a bunch of part time reservists or national guard doing a disaster recovery drill. If they are active duty, thank god, because they know wtf their doing. And the part timers should watch and learn.

I spent 20 years in the US sub force. Mid 80's to mid 00's. It's a drill people. We practice so we have a little understanding of what it takes to do our job when we are asked to do it. It's one thing to practice on your own. Get a whole bunch of different organizations involved and it gets complicated. In fact if not practiced in peace time it would be a disaster in time of war. We would be shooting ourselves as much as the enemy.

Just take this away from the drill. We practice. We learn how we can do things better. Then we practice that. All of which makes us the best military force in the world. And always in standby to serve when diplomacy breaks down.