People are interested in nuclear because it's zero carbon, because it's mature, and because it's suited to base load. It's the only zero carbon source that plugs right into the hole left by fossil fuels. IMO it's really that simple, and you can be pro-nuclear and also pro-renewables.

Personally, I don't really value solely economic arguments about power generation anymore. The cheapest power would be the best power if all the externalities were priced in. But they just never will be.