That would seem like reasonable thinking, but the type of people who want perpetual war won’t let a little thing like reason or thought get in the way.
If you really want perpetual war, the best/easiest way to accomplish that is to not have an enemy. Declare war on some vague concept that anyone could be accused of or related to (infidel, inferior race, communist sympathizer, terrorism), or on some common inanimate objects. That has the bonus of letting you target anyone you want. If things get dull, just shift the category or reclassify and add new items to it. There will always be plenty of vague concepts and inanimate objects.
It’s the international version of laws that make anyone a criminal and can therefore be selectively enforced to oppress whoever you want.
