Switzerland has national service for the reasons already listed on this thread, they also have every citizen keep a rifle in their homes, this is to prevent all the larger surrounding countries from just rolling over them, if they attempted it, they'd have a couple of million armed citizens to contend with who at least know the basics of how to fire a gun.
This is actually a smart move. This way they have a pretty solid defense already in place.
More countries should follow this example, although many aren't as rich nor as developed as they are.
Well as for Isreal, I don't like that women have to be forced into this. I guess as a man, this is very beneficial for most and 3 years isn't that long either.