The most striking line of the 2012 presidential campaign so far has come from Texas Gov. Rick Perry. "I'll work every day to make Washington, D.C., as inconsequential in your life as I can," he declared in his Saturday speech announcing his candidacy.

That line—notable for both its bluntness and crystalline clarity—neatly summarizes both why the Perry candidacy so excites many conservatives, and why some Republicans worry a Perry nomination might represent a bridge too far.

In...