The Union of Concerned Scientists has overturned its longstanding opposition to nuclear power. Other green groups should follow suit, says Mark Lynas

Nuclear power plants provide low-carbon power Leroy Francis/Getty

Changing your mind on a controversial topic isn’t easy, especially when you have spent decades campaigning against your new position. Which is why the decision by the Union of Concerned Scientists (UCS) to drop its long-standing opposition to nuclear power is so important, and why the organisation deserves great credit for having the courage to take this step.

The UCS has broken with the anti-nuclear ideology that has been part of the advocacy group’s DNA since the 1960s. The UCS isn’t campaigning for nuclear plants to be built, however. It has …