[chimera]

FWIW I think both serve a useful purpose. One can legitimately question specific programs, but the manned/unmanned divide is largely artificial. True, there are some places people just can't go right now, so unmanned missions are the ticket. OTOH, having that "Mark I Organic Computer" in the field and on-station allows you tremendous flexibility. A comparison of the Apollo vs. Surveyor or Lunakhod returns gives you a feel for that.

There are no reasons other than lack of will (guts, courage, vision) that we can't do both.

[Arkie2]

Manned programs haven't accomplished much of anything useful since the Apollo days. Orbiting the earth and servicing an ISS that is for the most part worthless doesn't constitute expanding the boundaries of knowledge.

There was one useful mission astronauts did carry out and that was satellite repair, in particular the Hubble. We can't even do that now with the new orbit restrictions on the shuttle. We're just spinning our wheels in the manned arena. Maybe Burt Rutan can make it work. NASA sure can't.