First of all, the New World is a very large place and the estimated population of Native Americans before colonization is 50 million - 1/6 the population of the USA alone. Have you ever driven through the USA? A lot of unused land, even now. One conclusion to draw is that there was a lot of available land at the time of colonization that was never homesteaded, also land that was abandoned. Consequently, a lot of colonization was finding unused land and building on it by the colonists. That was the vast majority of the story of colonization, it is just not the history on which people fixate. Native Americans do not have a property right to the entirety of the New World merely by being born on the continent. Thus, I reject the premise that “much of the land was acquired through violence and displacement.” Some of it certainly was, but much of the land was morally homesteaded by the colonists.

Regarding the land that was acquired by conquest, we don’t have a time machine. We cannot undo past evils. There is seems to be an implied premise that the Native American tribes were entirely peaceful and never acquired land by conquest and displacement. That premise is wrong. Humans have a history of violent conquest and morally illegitimate acquisitions of land, and this applies to many Native American tribal holdings. We cannot possibly redress that entire history, nor should we. The people alive now didn’t commit the atrocities. We recognize the evils that happened and strive toward a peaceful society, which you need Objectivist (or libertarian) principles to properly do.

How many of the conflict between Native Americans and colonists occurred because a nomadic tribe returned to a land they left decades ago and found colonists there, and initiated force against the colonists? Have you factored that into the historical analysis?

Lastly, why would the history of coercive human interactions have any effect on the grounding of libertarian ethics? You are implying the establishment of the libertarian moral framework is somehow tainted by historical human actions that violate that ethic - most of occurred before libertarian ethics were fully conceived. Why is that? Some land was unethically acquired, why does that concrete affect the philosophy? If anything libertarianism is a response to that history. Libertarian ethics is a break away from the jungle ethic of the past that lead to conquest and initiations of violence. You have to make the argument that the libertarian ethics are built on unjust foundations, you haven’t. The ethics are not hypocritical or contradictory at all.