With that money, you can build even more. The US might also send old crap as usual, and that's good for you because the missiles expire, and it costs a lot of money to demil them, sometimes close to the production price. And don't ignore the data you get from Ukraine using those missiles, this is how you get a better weapon system. You don't want to find out potential problems in a war with China, for example. Also, when other countries see what they can do, they'll order too. So you get money, jobs, intel, etc.