Do Good Fences Make Good Neighbors? addresses the historical impact of strategic barriers, defined here as "continuous or mutually supporting works denying the enemy avenues of attack across a front." In his introduction, Brent Sterling argues for the relevance of such an appraisal given the renewal of interest in strategic defense around the world (old fashioned walls, as well as more novel missile defenses) and the shallow debate surrounding it, the "dynamic" of which "is for critics and proponents to talk past each other, adding highly subjective versions of the past to bolster their arguments," with even normally circumspect historians "prone to apply sweeping characterizations on this topic.