Viewing history from one perspective can be utterly devastating. Like in the case of the Native Americans. If history was only shown in the point of view of the Europeans, we would have known how the Native Americans saw things. Viewing history from one perspective can leave a stigma, stereotype, or prejudice towards the other group.
In this image, two Native Americans are saying that we are honoring one terrorist, yet we are also condemning another. In this case of the image, we are honoring Columbus and condemning Osama Bin Laden and they're saying that it doesn't make any sense. It doesn't, what Columbus did to the Native Americans when he got here was completely horrible. Yet in some textbooks, Columbus is portrayed as a hero when in truth, he isn't. So viewing history from one perspective isn't great because we can't see things from a different from another group.