First, don't you mean Pre-WWII Japan instead of post WWII Japan?
Now the comment.
I don't think there is any correlation between either Education Level or Religion when it comes to violence.
There are far too many examples of educated people committing atrocious acts of violence as well as similar acts of violence committed in the name of Religion.
WWII is a classic example.
Despite what many believe, Pre-WWII Japan was a very well educated nation. It's science and industry was as good as any in the world. Simply look at the quality of products they produced and you can see that technologically, they were the equal of the US or Great Britain.
The same can be said of Germany. Again, education was superb and science and industry were as good as any other nation.
Yet these very well educated people, both Germans and Japanese committed some of the most horrific acts in the history of the world.
What is at least as important, both committed those acts in the name of religion. In Germany, the Nazis used Christianity as their primary justification while in Japan, it was a belief in a GOD/Emperor.
So neither Education or Religion is the Cause or Cure for violence.
People always want to jump straight to Hiroshima and Nagasaki as examples of horrific acts.
Actually, they were both relatively mild compared to what happened in both theaters of war. The fact that they each were caused by one individual bomb is something to unique and frightening, but beyond that, neither has much significance.
For example, if you look at the damage that was done to Swinemuende, Dresden, Hamburg, Cologne, Kassel and Wurzburg, you find far greater loss of civilian lives and far more destruction.
But again, what you folk point out is that there is little correlation between education or religion and violence and even less correlation between the two and Evil.