of power and is the key to dominating the Heartland. Paraphrasing MacKinder’s
summary of the Heartland theory, Spykman offered his own summary:
Who controls the Rimland rules Eurasia;
Who rules Eurasia controls the destinies of the world.Rimland theory differs from the Heartland theory in two major aspects. First,
Spykman believed that MacKinder had greatly exaggerated the prospects of the
Heartland as a base of power. Having the advantage of writing four decades after
MacKinder’s original thesis appeared as theGeographical Pivot of Historyin
1904, Spykman noted that the development of railway infrastructure in the Eur-
asian core area had not progressed in the way that MacKinder had expected in
his original thesis. Indeed, the quality and quantity of transportation linkages in
MacKinder’s Heartland, especially in Siberia and western China, had remained
at quite a low level, and could not compete with the sea transport of the inner
and outer crescents. In addition, Spykman criticized MacKinder’s conceptualiza-
tion of the Heartland as a repository of vital resources, especially because its agri-
cultural potential was much less than in the surrounding regions.
Second, Spykman pointed out that the Heartland theory oversimplified the
historical relationship between sea power and land power in regard to controlling
the heartland. Spykman admitted that the location of the Heartland provided a
defensive depth and presented daunting challenges to an invading adversary.
But this was well-known from a cursory review of Russian history (Russia being
the country occupying most of the Heartland), and this seemed to be almost the
only real geographical advantage the location enjoyed, vis-a`-vis the Rimland.
Spykman revealed that in fact the history between the Heartland and what he
called the Rimland was not based exclusively on the sea power of the Rimland
versus the land power of the Heartland. He cogently pointed out that various
alliances involving the Heartland power (he used Russia as an example) and coun-
tries in the Rimland had emerged over the course of modern international relations,
and that in fact Russia had on occasion joined with one or more Rimland powers to
counter the ambition of an aggressive Rimland country—World War I itself was a
case in point.
For Spykman, the key region for global control was the Rimland. This was
because the Rimland had to function as both a land power and a sea power, and
it also functioned as abuffer zonebetween the powers of the Heartland and the
naval powers of the outer islands and continents. It is strategically more important
than the Heartland due to its greaterpopulationand more advanced economy, two
geographic factors that he believed MacKinder had completely failed to consider.
Furthermore, the history of the balance of power on the Eurasian landmass, and
Rimland Theory 287