Much speculation is on going over Japan’s nuclear power plants, the effect on Japan and delaying using nuclear power. A few facts are in order and more are included in the attached link.
The nuclear power plants in Japan are built with Generation II technology and not the improved Generation III. Gen III technology is much improved and safer. A major nuclear event is not going to occur. This will not be a Chernobyl. There are major differences in the reactor designs, the management of reactors and the emergency responses of the countries.
Japan was hit with a catastrophe of major proportions consisting of (1) a huge earthquake and (2) a tsunami. Japan is one of the most earthquake regions in the world. it makes California look benign by comparison.
I lived in Pennsylvania (State College) during the Three Mile Island event. We were a 2 hour drive from Harrisburg, probably an hour straight line and there were no problems.
The China Syndrome where a nuclear reactor melts down all the way through the earth to China cannot now or either occur. It makes for a an intriguing movie. And by the way, I do not know about Japan, but China is not under the United States on a straight line through the earth.