Serious work on commercial fusion began 70 years ago. Ever since, it's been "about 20 years away". And - who says it'll be limitless? (I know, it'll also be saf

Serious work on commercial fusion began 70 years ago. Ever since, it's been "about 20 years away". And - who says it'll be limitless? (I know, it'll also be safe, clean, and too cheap to meter.)