[el_zorro]

I don't think it is so much an issue of ability so much as desire. Most of the tech has been dreamed up for decades, but it needs funding and a green light (particularly the nuclear reactor, given that there were protests about even Curiosity's RTG).

Personally, I think there's a huge amount of talent just waiting for the right moment to strike, and then the whole Mars thing is going to burst right open.