By whom?

> proliferation

Unlike firearms, the critical and expensive part of these weapons is the round, not the launcher. And they're being used up at a huge rate.

What exactly is the worry scenario, that after the war is over the Ukranian state, newly forged in adversity, will immediately lose operational control over its units which will then decide they aren't imminently going to need these weapons for homeland defence, so they can sell them on the black market?