Mxsmanic wrote:

Different people enlist for different reasons. Some of them do indeed
have a desire to kill, but certainly not all.

Some who DON't enlist have a desire to kill....
But it is harder to detect them in civilianhood and weed them out.

In a room full of guys with guns, who have to depend on each other, I
can't imagine much that would be scarier than someone who sits alone
mumbling "Kill, kill, kill".