Not even necessarily then. Wars divert resources such as metals, chemicals, food, to be consumed overseas instead of in better economic activity. The US has been in wars for decades, adding trillions to the current debt and trillions more to future liability. Those trillions spent on infrastructure, science, education, etc., would have had a far better effect on the lives of people in the US than spending it on wars.

Think of the amount - trillions already spent on war. And trillions more in debt because of it.