I strongly disapprove of the "send a man to Mars!" thing Bush went in for, because it was just a publicity/ego-boost stunt for him, but I know how much damage it's done to the unmanned programme. It might have actually been a useful programme in terms of developing new technology, but they weren't given any extra money to do it. Instead they had to strip the existing programmes for money, and as a result they've lost teams and pools of expertise that simply can't be replaced. Scientists who've been made redundant don't just sit around waiting until they're wanted again; they find other jobs, and they don't come back. It will take decades to undo that damage.