I would agree with you if I thought the shuttle and the ISS were anything more than a politically inspired waste of money. I'm actually a big fan of space exploration but we've been off track since Apollo except for the robotic missions which have returned an abundance of science. Maybe Griffin can get it back on track but I'm not willing to bet against future political interference taking us down another dead end road.
BTW, I think the robotic missions are fine, too, so perhaps my "tinker toys" comment should be taken in context. I see no reason why a robust program of exploration and development could not encompass both a manned and a robotic component. There are just some things that people do better than robots right now. Likewise, there are places where people cannot go right now and it makes sense to send machines there first if we want to learn about them.