You are correct about the ammo. But the hardware is being brought out of mothballs, most of it was never going to be used again. Old versions of tanks, AFVs, etc. They saved us the cost of storing and -eventually- scrapping them. The lion's share of the dollars quoted is the accounting value of that hardware.

But, yes...new equipment largely uses the same ammo as the old. NATO standard shells, etc. We will need to produce more. Which is good for jobs, obviously. And corporate bottom-lines.

What happens if we need them? By tying-up Russia in Ukraine, we reduce the likelihood that we will need them. Russia is too occupied to stir-up trouble elsewhere, and their military is getting weaker by the day. Readiness has gone way down.

The ramifications if Russia is able to force Ukraine to accept a crappy deal (which is more likely now) would be far-reaching and very negative for future peace in the world, and Europe.