There have been two significant accidents at nuclear power plants in modern history. A near-meltdown at Three Mile Island in 1979 was followed seven years later by an explosion at Chernobyl in Ukraine. Both led to sharp declines in support for nuclear power.

It is too early to say what impact the failure at Fukushima in Japan may have. The authorities are still battling to make the plant safe after earthquake damage caused the cooling system to fail in two reactors, damaging their cores. But already the world has seen chilling images of explosions at the facility, and stories are circulating about workers having been exposed to radiation. A catastrophic meltdown is a sombre possibility.

So far, the authorities have been relatively open. They have also been decisive; evacuating people and flooding reactors with seawater to contain the build-up of heat.