Nuclear is so back. America’s birthday gift to itself just went critical.

For the first time in more than 40 years, privately developed nuclear reactors are switching on in America.

On June 4, Antares Nuclear’s Mark-0 reactor went critical at the Department of Energy’s Idaho National Laboratory. Valar Atomics followed on June 18, producing heat from a reactor core inside a tentlike structure in the Utah desert. The Department of Energy called it “the rebirth of America’s nuclear industry.”

‘Nuclear in America has been defined for too long by delays, by companies that said they would and then didn’t. … Today is the first of those commitments delivered.’

President Trump has long been skeptical of large traditional reactors, saying they tend to get “too big and too complex and too expensive.” But he bet big on small modular reactors, pledging