The Mitzva of making Aliya is alluded to at the end of Parshat מסעי and again in Parshat דברים. In מסעי it's written, והורשתם את הארץ, "And you shall inherit the land." And in דברים it's written, עלה רש, "Go up and inherit it.״ The Ramban says that it is a positive commandment to settle in Israel.
The section in מסעי comes with a warning. In במדבר 33:55, it is written,"But if you do not drive out the inhabitants of the land before you, those of whom you leave, shall be as pins in your eyes and as thorn-hedges at your sides. And they will harass you upon the land in which you dwell."
Obviously, we cannot say that the Torah is racist, G-d forbid. Nevertheless, the purity of the land must be maintained. Ultimately, only those who achieve גר תושב status by observing the Noachide laws, are permitted to be here. Those who do not will not be allowed to remain. We must remember that the Torah is the epitome of righteousness and perfection. Removing the impurities that defile our land, is the most merciful act one can do.