At what point is ok or even necessary to declare war and enforce physical violence on a nation or group in self defense of the economic whole?
at the point where america started a civil war due to the british trying to impose taxes on us imports many hundreds of years ago
at the point where africans started civil wars due to the land theft and hyperinflation games of their own government allowing multi-nations to invade and mess with their economy in the last 100 years
at the point of oil reserves getting low causing the US to invade the middle east many times in the last 40 years
as for if its OK. depends who you are asking.
for the government that get a nice tax income from war, they believe its worth the cost of life.
if you ask the army recruits. well it depends what mantra their recruiters told them concerning how the war is their patriotic duty and can save lives(pfft)
if you ask civilians in general. well depends if they are going to get cheap produce due to the loss of life