The Geopolitical Role of the Three Seas Initiative: Mackinder’s ‘Middle Tier’ Strategy Redux

Abstract

The Three Seas Initiative (TSI) is a forum of Baltic, Black and Adriatic sea countries. In 1919, pioneering British geopolitical theorist Halford J. Mackinder promoted a ‘Middle Tier’ strategy, that paralleled the Polish interwar ‘Intermarium’ project. Today, the United States views the TSI as an asset in the ‘New Europe’, while pro-Atlanticist Central and Eastern European states see it as a tool to build transatlantic connections. This article suggests that the TSI revives Mackinder’s ‘Middle Tier’ strategy. Similar to how the Franco–British bonds with the ‘Middle Tier’ states sought to offset Germany and Russia a century ago, today stronger ties between the US and the ‘New Europe’ within the TSI strengthen the position of NATO vis-à-vis the EU, rebalance Western EU actors and counter Russian interests.