According to Mackinder, Earth's land surface was divisible into: The Heartland lays at the centre of the World Island, stretching from the Volga to the Yangtze and from the Arctic to the Himalayas.

One of Mackinder's personal objectives was to warn Britain that its traditional reliance on sea power would become a weakness as improved land transport opened up the Heartland for invasion and/or industrialisation (Sempa, 2000).

[4] Signs of Mackinder's Heartland Theory can be found in "Crush zone" of James Fairgrieve, Rimland of Nicholas Spykman, "Shutterbelt" of Saul Cohen and the Intermediate Region of Dimitri Kitsikis.

Mackinder's term became a popular buzzword[citation needed] after Obama's Secretary of State Hillary Clinton authored "America's Pacific Century," in Foreign Policy.

'"[7] K. S. Gadzhev, in his book Introduction to Geopolitics (Введение в геополитику, Vvedenie v geopolitiku), raises a series of objections to Mackinder's Heartland; to start with that the significance physiography is given there for political strategy is a form of geographical determinism.

Such argument of the critics [however] is hardly found out because a variety of literatures repeatedly cites the geostrategic importance for USA security in fighting terrorism and preventing Russian dominance…"[4] According to Matt Rosenberg, Mackinder's theory was never fully proven[9] as no singular power in history has had control of all three of the regions at the same time.

The closest this ever occurred was during the Crimean War (1853–1856) whereby Russia attempted to fight for control over crumbling parts of the Ottoman Empire, ultimately losing to the French and the British.