America’s extended nuclear deterrent has always rested on credibility. Credibility is one of those intangible factors in international relations that can mean the difference between peace and war and victory or defeat. Credibility is sort of like obscenity — it…

For about 60 years, we’ve been told that commercialized fusion is 30 years away. Latest predictions? Oh, about 30 years away. But there’s been much brouhaha over what’s been called  “game-changing,” “transformative,” and “a moment of history” in the field….