When the SSC was cancelled, I decided I never wanted to be a scientist (I was 15 or so); it would be so horrible to work on a program like this and be entirely dependent upon the government for funding, then have it killed. Entrepreneurship seems much more incremental; if you raise 50% as much money, you can still often do things, just with more risk and pain; if you have a big grant funded science project, 50% in getting it funded gets you very little more than 0% success.