According to Spykman's Rimland Theory, which area is strategically most important for controlling Eurasia?

According to Spykman's Rimland Theory, the area strategically most important for controlling Eurasia is the Rimland itself. Nicholas Spykman, a Dutch-American geostrategist, developed the Rimland Theory as a critique and modification of Mackinder's Heartland Theory. Spykman defined the Rimland as the coastal areas surrounding the Eurasian Heartland. This includes Western Europe, the Middle East, South Asia, and Southeast Asia. Unlike Mackinder, who emphasized the importance of the landlocked Heartland, Spykman argued that the Rimland was more crucial because it was a buffer zone between the Heartland and the sea. The Rimland contained a higher concentration of population, resources, and industrial capacity compared to the Heartland, making it strategically more valuable. Spykman's famous quote summarizes his theory: 'Who controls the Rimland rules Eurasia; who rules Eurasia controls the destinies of the world.' He believed that control of the Rimland would provide a state with the necessary resources and strategic positioning to dominate Eurasia. This is because the Rimland offers access to both the sea and the interior of Eurasia, allowing a power to project its influence in multiple directions. Spykman argued that the Rimland was neither entirely land power nor sea power, but a hybrid zone that could be controlled by either. He also noted that the Rimland was prone to instability and conflict due to the competing interests of various powers. Therefore, controlling the Rimland was essential for maintaining stability and preventing any single power from dominating Eurasia. The United States' Cold War strategy of containment, which aimed to prevent the spread of Soviet influence, was heavily influenced by Spykman's Rimland Theory. The US formed alliances and established military bases in key Rimland countries to contain the Soviet Union, which controlled much of the Heartland.