What's war spending?

Countries aiming for world unification and hegemony; countries that have been invaded before and made great sacrifices. Each country is heavily armed with logical excuses.
It goes without arguments that all weapons are killing devices and deny the very existence of humans.
In today's world where information transmission pervades every corner of the world and a common concept of peace is recognized among us, we cannot help doubting that such ugly equipments are produced and used even now.
Killing weapons are primarily explosives, and when used they are only scattered as smoke and garbage and are a waste of resources with no productivity. Machinery and explosive are useless after the battle was settled and weapons that were not used in the turmoil. It's clear that they are going to the black market and falling into the hands of terrorists
As a result, repeated conflicts and mayhem will continue endlessly.
Things aren't as simple as making a donation to the side we feel pity and sorry for being put on propaganda, if we are not familiar with international conflicts.