While I was going to community college in the late 90's, I had an IT consulting biz where I serviced mechanical engineers and folks in the US nuclear industry who were ex-General Electric (GE NE). I learned nuclear was heavily-regulated (rightfully so) and costly but the main barriers to new sites were insurance, the huge capital investment, and the very long project cycles. As such, these are just too risky for most business people and investors. Nowadays, even with SMRs, the ROI still doesn't make sense given the massive, massive advances in renewables and regional grid storage. Very few Americans want an unproven, fly-by-night startup SMR in their neighborhood or in their county. I'd be okay with just a few mega reactors in fixed sites in very remote areas that would be heavily defended with perimeter security and anti-aircraft/-drone emplacements. I'm not okay with SMRs on flatbed trailers with minimal security in urban areas.