That was two years ago, so has it, by now?
That's not especially powerful either, less than 0.5 Megatonne TNT-equivalent.
Nuclear hydrogen-fusion bombs, especially, are far more powerful than the <20kt uranium-fission weapons used on Japan, and America was testing fusion bombs of some Mt "yield" in the 1950s-60s.
The USSR even tested one hydrogen-fusion bomb it named the "Tsar Bomba", of about 50Mt, air-dropped over the uninhabited northern island of Novaya Zemlya. It seems to have been intended as a proof of ability rather than as a "production" weapon: dangerous to the air-crew, and too big and heavy to be a ballistic-missile warhead.
So there is nothing new in the reported power.
Instead, what is far more alarming is that the USA should even think of reviving them, with obvious likely copy-cat replies from Russia, China, etc.; instead of striving to eradicate such weapons.