Geostrategy, a subfield of geopolitics, is a type of foreign policy guided principally by geographical factors as they inform, constrain, or affect political and military planning. As with all strategies, geostrategy is concerned with matching means to ends Strategy is as intertwined with geography as geography is with nationhood, or as Colin S. Gray and Geoffrey Sloan state it, "[geography is] the mother of strategy."
Geostrategists, as distinct from geopoliticians, approach geopolitics from a nationalist point of view. Geostrategies are relevant principally to the context in which they were devised: the strategist's nation, the historically rooted national impulses, the strength of the country's resources, the scope of the country's goals, the political geography of the time period, and the technological factors that affect military, political, economic, and cultural engagement. Geostrategy can function prescriptively, advocating foreign policy based on geographic and historical factors, analytically, describing how foreign policy is shaped by geography and history, or predictively, projecting a country's future foreign policy decisions and outcomes.
Many geostrategists are also geographers, specializing in subfields of geography, such as human geography, political geography, economic geography, cultural geography, military geography, and strategic geography. Geostrategy is most closely related to strategic geography.
Especially following World War II, some scholars divide geostrategy into two schools: the uniquely German organic state theory; and, the broader Anglo-American geostrategies.
Most definitions of geostrategy below emphasize the merger of strategic considerations with geopolitical factors. While geopolitics is ostensibly neutral — examining the geographic and political features of different regions, especially the impact of geography on politics — geostrategy involves comprehensive planning, assigning means for achieving national goals or securing assets of military or political significance.