The gas squeeze this winter is the harsher episode yet in this “cold war” triggered by Moscow. Alongside human discomfort, the prolonged gas cut-off amid an Arctic cold snap has halted much industry in Eastern Europe. As the stakes rise, this Stratfor article lays out clearly the interests and leverage of all sides – Russia, and Ukraine, NATO and the EU. Moscow’s goal is to halt further efforts to extend NATO or EU membership to Ukraine. In using energy as a weapon, Premier Putin’s team demonstrates a detailed mastery of the natural gas infrastructure. Moscow insists that Ukraine needs to add gas from its own inventory into the pipelines running west to get enough pressure for the Russian exports to reach their customers in Europe. Russian pressure may backfire by goading Europeans into making investments to diversify their sources of supply. But so far the main reaction has been moves to restart nuclear plants in Eastern Europe that were shut down for safety reasons when these states were admitted to the EU.