Army cadets then army? To avoid putting him in dangerous situations? Bl**dy hell naz, that's a cracker, yeah just send him out as cannon fodder that'll sort the young whipper snapper out!
Seriously, before he listens to anything you say, you need to do some very serious listening to him and find out exactly what his problems are. Treat him with maturity and respect, take on board what he says to you and try to reach compromises about it. If he's unaware of danger then he needs it undramatically pointing out to him, as at 13 he's going to start to want to go out and take more responsibility for himself in preparation for adulthood. Keep things calm and communicative and see how it goes. If it's still making no difference after a couple of weeks you need to reconsider your options, but generally it's true of most difficult teens that if you treat them with maturity and respect then they treat you the same and will understand why you'd prefer them to behave in certain ways.Good luck.