We can very much afford what we're putting into Ukraine. Much of that value is the original sticker price of old or used equipment the US will replace anyway. The embarrassment of the Russian military is a huge windfall for the American defense industry. Poland alone tried to order 500 HIMARS which we can't even supply. All the weapons systems we sell will in turn generate billions in service contracts, eventual upgrades, and ammunition purchases that goes right back to the American economy.

Combine all that with neutering the Russian military and strengthening NATO unity; while putting zero American troops in harm's way. This has been the bargain of the century.