"But people make choices because of their experiences, and the details of their specific situation and circumstances."
You make it sound as if we're organic robots - input circumstances and obtain the computed decision. Such a view makes concepts such as morals and responsibility (and, implicitly, our discussion) irrelevant, inapplicable to humans.
I don't agree with this notion at all.
Hitler rose to power due to economic conditions (partly) - but what did he do with that power?
"Japan itself had become a major world empire in part because of its desire to avoid becoming one of the many oppressed colonies" - and then graduated to doing some oppression ot its own.