War is used to open up new markets, garner more resources for yourself, cut markets off from competitors, cut competitors off from resources.
The Opium Wars in China, all three of them, fought to create that market, and keep it alive. The whole Colonial Era just a gigantic global war. Euros taking land and resources, but first have to drive off, or enslave/subjugate the natives. The Banana Wars are keeping ever flowing supply of bananas at cheap rates which is good for business. Etc, etc.
Well, okay, War does hurt your business if you losing, or will lose it. But if you can win it, then it is great for your business. But no one attacks anyone if they know they no chance of winning.