> Even when an active war is on, those in charge have learned to limit the length of time a soldier spends in warzone to 1 year. Like US did in Vietnam war.

This is absolutely false. It may have been true in Vietnam, but that has to do more with there being a near infinite source of soldiers (the draft) and also an insane amount of soldiers being killed an maimed and unable to take a 2nd term.

In Afghanistan and Iraq, I knew people who were serving five or six tours.