Reality check: The jetstream moves from West (Japan) to East (U.S.). Radiation comes to us as fallout and bio-accumulates. A little here, a little there, repeat. Giant shrimp, animal die-offs. Radiations lasts from decades to thousands of years. There is no safe level of radiation. Your ignorance is proof why human is facing annihilation: there are just too many stupid humans on the planets. Forrest Gump said it best: Stupid is as stupid does. He learned that from his mama.