Four years ago, a devastating tsunami crashed into the coast of Japan. Waves 15 meters high breached the seawall of the Fukushima No. 1 nuclear power plant, cutting off its emergency power supply and disabling its cooling systems.
The nuclear accident was the worst since the meltdown of the Chernobyl power plant in 1986. Investigators concluded that one of the underlying causes was complacency: Those in charge of the facility believed that their safety systems were robust, and there was no effective independent oversight.
The disaster in Japan has spurred reforms in the field of nuclear safety. But when it comes to nuclear security, complacency remains a major problem. We must not wait until tragedy strikes to do something about it.