Why did the Washington Post publish George Will's immigration rant?

From George F. Will's April 28 Washington Post column:

Non-Hispanic Arizonans of all sorts live congenially with all sorts of persons of Hispanic descent. These include some whose ancestors got to Arizona before statehood -- some even before it was a territory. They were in America before most Americans' ancestors arrived. Arizonans should not be judged disdainfully and from a distance by people whose closest contacts with Hispanics are with fine men and women who trim their lawns and put plates in front of them at restaurants, not with illegal immigrants passing through their back yards at 3 a.m.

h/t Atrios