Well, spears and swords have been around for
millennia and are still being used to kill people. If we waited for
morals to catch up with technology, mankind would probably have become a footnote of history, a rather lame species which existed on the
African plains for about 20 years before
extinction. People will do good or evil, whether it's with the latest
technology or not.
We have a lot to be proud of, actually. We've known about U-235 for more than 50 years and still haven't eradicated ourselves. Go us!