Many nuclear physicists, for example, still insist that nuclear power is safe. In a world governed only by science, they would be correct. But the world is run by people, not principles, and no mathematical equation, however elegant, can explain how the management of nuclear installations can be prevented from taking shortcuts, when the shortcut is many times cheaper than the safe procedure. Nor can science tell us how we could achieve the 10,000 years of political and economic stability required to ensure that nuclear waste is managed safely, when no honest politician can promise 10. Nuclear power is inherently dangerous, not because it can't be made safe, but because it won't be made safe.
Environmental issues are always multi-factorial.
The more specialised our researchers become, the less likely they are to understand them. Their inability to perceive the wider consequences of their work has led some scientists to treat the anxious public with contempt. Sometimes my young son wants to cross the road when it's dangerous - sometimes you have to tell people what's best for them. Offensive and patronising as such statements are, I find it hard wholly to blame the authors. Early specialisation has reduced many of our scientific debates to a dialogue of the deaf.