If you were in the local area, that would be warranted and, in fact, gov't officials have said they are making it available to locals near the plant in Japan. Keep in mind they ordered evacuations of a 10km radius many hours ago and just extended the existing evacuation era for the 2nd plant to 10km as well.
Do you need KI in the lower 48, 5000 miles away? No, certainly not now. You'd be doing far more harm than good.
Take 50-85MG for a few days in preperation won’t do any harm and in fact this is the time to take it for a few days.
Flood your system.