You're conflating expected value with investment cost. Your argument has the same merit as "I need a car to get to a this new job which will cost $1000 and I'l

You're conflating expected value with investment cost. Your argument has the same merit as "I need a car to get to a this new job which will cost $1000 and I'll make $100k more." If instead you purchase a car costing you $10k that doesn't mean it's no longer worth taking the job. This project has advanced our ability to build complex devices, and refined various manufacturing processes that will all have meaningful impacts on our economy and that is before it has started it's mission. The data it will collect is potentially invaluable not to mention the personal inspiration that projects like these inspire in individuals. Compare this to other ways that our government might have actually spent this $10B over the lifetime of this project and we're still getting a bargain. Compared to other NASA projects we likely wouldn't have gotten the manufacturing processes or complex integration experience and even more likely we wouldn't have gotten the inspiration. Bigger and more expensive projects are expensive because they're hard. When we succeed in doing hard things and even make the same thing easier in the future we collectively absolutely get more value.