I guess it depends on perspective. On one hand, it's an enormous amount of land - on the other hand, the USA is extremely big. I personally think the footprint is significant. It's not like we'd tear down suberbs to make solar farms, we'd tear down nature (undeveloped land).

The cost being the motivator that makes solar better than nuclear I don't believe to be accurate. Short term, solar is cheaper, but also we're making panels as fast as we can. It takes a lot of materials and is hard to scale quickly, so we can't just decide we want to switch the USA to solar and think we'll have enough panels in a decade even.

Additionally, nuclear isn't expensive in the long run. It's quite profitable and low maintenance. Nuclear waste is blown up by people who don't understand it. And our grid is ready to be powered by nuclear. Our grid can't yet handle the quick variablility of solar. If that weren't a problem, we still need additional power from events where there isn't a lot of sun for a while. Batteries may get us through the night someday (also another enormous manufacturing feat) but they won't get us through the week.

If both can be profitable, it's really a question of what we want to build. I argue that we can't even run off solar yet without some new technologies being made. Nuclear is the quick fix we need. The only reason we don't have it already is because of attitude towards it ("not in my backyard"), which I think would be different if people understood it.