To put this in perspective, Russian leaders ardently believe that they are the victims of a U.S.-led drive by NATO to encircle their country and diminish its international influence. They point, in particular, to the build-up of NATO forces in the Baltic countries, involving the semi-permanent deployment of combat battalions in what was once the territory of the Soviet Union, and in apparent violation of promises made to Gorbachev in 1990 that NATO would not do so. As a result, Russia has been bolstering its defenses in areas bordering Ukraine and the Baltic states, and training its troops for a possible clash with the NATO forces stationed there.