See the forest despite the trees. For this time, the very idea of punishing white men for doing shit to African natives in itself was a few light years forward, so cut Hanks some slack. You wouldn't see this again till the story of T'Challa and Klaw. Usually "natives" were pretty much always a threat to be eradicated, even in Grape Nuts ads: http://www.seanbaby.com/comicads/comicads39.shtml
The very fact that Fantomah defended them rather than the white invaders makes the strip pretty remarkable for 1940.