Mr. Moore, you're way off base. The Shuttle program was canceled by the Bush administration long ago, when external tank production was shut down. And we don't have a replacement for it because... Oh, wait, we do have a replacement! It's called Soyuz if you're referring to personnel transport, or every other launch system out there for cargo. These solutions cost far, far less than the shuttle. Maybe a better question is: Why did we need to spend all our money on the F-22, F-35, B-2, and many other overpowered military systems instead of boosting NASA's budget so they could develop a follow-on to the Shuttle that wasn't such a money sink? But no, NASA only got enough funding to pay for the shuttle, and later the badly-managed Constellation programs. They're just treated like a pork-barrel program Senators use to get reelected.