Who says nuclear is carbon neutral? It definitely has a footprint. But so does solar, wind, and hydro. All 4 of which are extremely small though. The advantage nuclear has over the other two is that it can generate power 24/7, it can vary its output, and it has a small footprint on land usage per kilowatt-hour it produces.

AFAIK there are no high energy producers that are end-to-end carbon neutral (or negative). Doing so needs some type of sequestration.