Jeff Faust recently commented on a speech by Michael Griffin. I think he is wrong in one respect, in what he said. I seem to recall he has said the same kind of thing before. It is completely untrue that the USA would gain standing in the world by giving up its manned spaceflight program in favour of concentrating on internal affairs such as climate change, healthcare etc.
I don't know about western Europe, but in my experience the average person outside of the USA is surprisingly uninterested in the US participation in Kyoto and degree of participation in alternative energy research, or other fashionable activities. The US manned space program has a highly visible iconic (it is associated with a number of iconic images, such as the space shuttle launch, and the planting of the US flag on the moon) presence that is recognized and celebrated the world over. It probably doesn't hurt that it is also run by a civilian organization. Amongst average people around the world, and certainly here in Korea, it is seen as one of those things that is distinctly American, in the best possible sense.
In fact, I would go so far as to say that if the US were to willingly give up its lead in crewed spaceflight, it would probably be seen as somewhat strange, and a symptom of some unrevealed weakness. I certainly can't see any respect being gained from it.