This is a Keynesian argument, which has largely been disproved. Keynes famously said if you just paid people to dig holes and fill them back up again, that this would be net stimulative to the government. It works until it doesn't work, because digging holes, as you can reason from common sense, does not actually create value.

This U.S. operation is meant to bomb the Iranians into the Stone Age, so presumably THAAD-level air defense wouldn't be needed again. The Qataris, Saudis would have sold off to South Korea, Taiwan if they wanted.