Why wasn't there looting and increased violence after the tsunami in Japan like there was after Katrina?

I am writing a report for college about the earthquake and Tsunami in Japan. Part of my report is how the Japanese victims of the tragedy coped with the tragedy in the following weeks. I know after Hurricane Katrina there was a sharp increase in rape, looting, and many other types of violence following the Hurricane. Can anyone shed some light on why the Japanese people didn't engage in such behavior after the Tsunami? I am at a loss on this one. Thanks for any opinions.