I imagine that JTF'ers seek to be prepared, should combat be a necessity.
I find combat simulations/games on the PC, XBox or XBox 360 to be helpful in training the mind to think tactically.
I'm currently playing Call of Duty 4 on the XBox 360. In some ways it is very realistic, in others not so.
Anyone wanna join me? We could fly the [JTF] "clan tag" in front of our names.
Best overall simulation is "Battleground Europe". The technology is older, but the same principles apply, and there's no other sim like it. You wage war on a 1/2 scale map of Europe. Players are operating aircraft, armored vehicles, AA guns, various man-portable weaponry, even naval vessels.
This means that while you're trying to defend an Army base from tanks and infantry that are slowly closing in, you might be getting dive-bombed by Stukas, while your buddies are trying to shoot them down with AA guns.
You'll need at least 1 Gig of RAM and a broadband connection to get a satisfying experience out of Battleground Europe (old name "World War II Online").
Costs less to get an XBox 360, subscribe to XBox Live, using your broadband connection. (Just make sure to get a "swap-out program" for the 360, as these things are notorious for going belly up within a year. Of course, you might get lucky.)
Else, I can meet you on an old black XBox (you'll have to get one used, probably) with a copy of Operation Flashpoint: Elite. OFP:E is the closest thing to Battleground Europe you'll get on an inexpensive gaming console, and it simulates modern technology.