Which really brings up the question of having a charity based social support structure instead of just delegating that to the government and letting a few hundred million required to run the entire thing be written off as a sig fig error of the military budget.
Annual donations to charity per year in the US are in excess of 400 Billion (so about 1000x more than your off the cuff estimate). Rather than being a rounding error in the military budget, this is about 2/3rds of total.
> Annual donations to charity per year in the US are in excess of 400 Billion
Yes, but how much of that is "social support" versus, say, wealthy people structuring expenditures they were going to make anyway to be more tax efficient.