Defining characterisitc of sovereignty?

I don't think this is what "most would consider the defining characteristic of sovereignty" but Scalia does seem to want everyone off his lawn so.... okay, then.

Update:  Scalia adds:

Notwithstanding “[t]he myth of an era of unrestricted immigration” in the first 100 years of the Republic, the States enacted numerous laws restricting the immigration of certain classes of aliens, including convicted crimi­nals, indigents, persons with contagious diseases, and (in Southern States) freed blacks. Neuman, The Lost Century of American Immigration (1776–1875), 93 Colum. L. Rev. 1833, 1835, 1841–1880 (1993). State laws not only pro­ vided for the removal of unwanted immigrants but also imposed penalties on unlawfully present aliens and those who aided their immigration.

In other words, Justice Scalia just cited the good old days of "Sundown towns" in defense of Arizona's immigration policy.

Upperdate: I should add that Scalia, in addition to endorsing laws of racial exclusion, is confused about where most of these laws were written.  Take a look at James Loewen's database of Sundown Towns and compare the Southern States with those in the Midwest.  Freed blacks weren't being shoved out of the South, they were leaving out of their own volition only to find themselves classified as aliens in the "sovereign" northern states they migrated to.