That's really impossible to say, we simply don't know what the economy would have looked like without the deficit spending. With the large budget imbalances we

That's really impossible to say, we simply don't know what the economy would have looked like without the deficit spending. With the large budget imbalances we've seen recently it seems reasonable to expect that increase in the money supply and new demand to have some impact of the economy. If it didn't, I'd argue we need to fundamentally rethink the core concepts of economics all together. Now whether the spending was a larger than the impact of wars I have no idea. I'd also be very suspicious of any research that attempts to model such a drastic alternate reality and come up with any meaningful comparison.