Well I would be surprised if a country would actually start a full scale war with an other country right now. It's just not smart because you'll probably get the UN against you for starting it. Gurillia warfare on the other hand isn't that easy to overcome simply by sending troops. There's no "homeland" to bomb, no gouvernment to nagotiate with. For those people that wan't to change the world (or just there backjard) with violence, that's the way to do it.
"It is not supreme excellence to fight and conquer in all your battles,
It is supreme excellence if you break the enemy's resistance without fighting."
Sun Tzu, the Art of War