That’s the wrong measure by a long shot.

If I lose a $2000 rifle, and that rifle is then used to massacre a school, was the loss a mere $2000?

If you lost a thousand $2000 rifles, then the loss was a "mere" 0.1%. Plus or minus an order of magnitude (or two).

I mean, like, you are implying the other 99.9% of spending on the war was harmless or salutary?

No. I’m just saying that they used the money that we lost to gain strength and power, and they used those weapons to kill us and many others. Gaining power and resources provided them with the ability to leverage that and grow even more, and to fund new criminal enterprises. Focusing on the relatively small dollar amount we lost to them initially doesn’t really capture the total loss.

I think this is getting into the same territory as the difference between owing a bank a hundred bucks and a hundred million bucks.