If the Iranians had this wonderful technological edge over the rest of the world, and they were about to produce a nuclear reactor that does fusion in a commercially viable fashion, bless them," said Ottolenghi. "But, the fact that nobody else has done it so far suggests that maybe the Iranians are up to just playful banter. However, if one looks at what the reality of a military program is, if you want to have thermonuclear weapons, you need to master the technology for fusion. And while fusion is not commercially viable for civilian purposes, fusion allows you to build infinitely more powerful nuclear weapons."