On April 15, two alleged terrorists in Boston killed three people, injured more than 170 others and terrified a nation ¡ª for about $100 it cost them to modify pressure cookers into bombs. We should be glad they didn¡¯t come to Japan, where they may have been able to explode a ready-made nuclear dirty bomb, kill untold thousands, render huge swaths of the country uninhabitable ¡ª and get paid by Tokyo Electric Power Co. (Tepco) in the process.

I wish I were kidding. Japan has more than 50 gigantic nuclear ¡°pressure cookers¡± ripe for exploitation by terrorists. And they wouldn¡¯t even have to lay siege to the facilities. Instead, they could just walk into a nuclear plant and leave with enough weapons-grade plutonium for a small atomic device ¡ª which later could be detonated wherever they chose. How?

In Japan, getting access to a nuclear power plant is very simple: fill out a job application.