The concept of Aztlan--if one is to assume it ever existed--differs quite a bit from the position of the Irish Republicans in a number of ways. First of all, one has to assume the (if's) are givens, and then realize that the area in question wasn't taken by force of arms and then repatriotized by people planted there from another area as a matter of policy.

             The original inhabitants were never part of one single group of people, there were many tribes and they died off from disease prior to the arrival of Europeans--the European diseases preceded them. The Europeans came from different places, not all representing a single government, and they fought wars between themselves. In addition there were people from other places--Asia and Africa.

             The resistance was never unified once the take over started, because it was never unified before he take over started.