I think it is useful.

Economies can not just switch into wartime economies on a dime. It takes a lot of time and a hell of a lot of changes to occur before a spike in demand flows back into a spike in production. And any spike in demand in Western Europe will be noticed by Russia and met with a spike in demand by Russia. It might be very hard to catch up.

Now I think US production of weapons is pretty high, and the US is making moves to increase and distribute wartime production. They just brought Japan onboard to make jet fighters.