The analogy is like iodized salt vs iodine tablet.
- Chernobyl exploded to the sky/air, and wind carried the nuclear waste away. There is no chance Fukushima will explode, even in the worse case of a melt-down. The difference between the recommended circle of evacuation we heard, from US vs Japanese guidelines, are 80km vs 20km. an 80km circle is about the size of Hong Kong. So people in Tokyo will be safe, very safe.
- The inner steel-concrete is intact. Yes, there is a theoretical possibility that there might be a leak, and risk if temperature will rise. The truth is once such risk arises, cement can be poured in to seal the reactors permanently. Worse case: the 50km radius or so will be no man zone, mainly a a result of radiation level risk -- but a paradise for wildlife.
- (As the New Scientists put it)
Why Fukushima Daiichi won't be another Chernobyl