Maybe we should have Hitler day as well - he probably had more to do than anyone with transforming the US from its gray post-Depression days to the vibrant superpower it became.
Well he certainly taught us a valuable lesson about the twin follies of indifference and appeasement.
I recently visited a village here in North America that has been more-or-less continually inhabited by the same people for ~12,000-13,000 years, and possibly a few thousand years longer. They still have a rich oral history...