The Story Behind Putin's Mistrust of the West

In many ways, Russia's current defiant geopolitical stance can be traced to a decisive moment in recent history: the belief that the West broke its promises not to expand the North Atlantic Treaty Organization eastwards. But experts argue over what exactly was promised, NATO itself calls the story of the broken promise a "myth," and the former Soviet president, Mikhail Gorbachev, who is critical of NATO expansion, has said the West kept all its binding commitments following from the reunification of Germany.

Now, George Washington University has taken a major step toward clarifying what exactly was promised and how, collecting a wealth of documents, all declassified in recent years, from the time Germany's reunification was negotiated. The many redactions -- the U.S. has way too many secrets, as National Security Archive head Tom Blanton pointed out in a recent interview with my Bloomberg View colleague James Gibney -- may hide important bits of the story. But even with them, the collection shows that top officials from the U.S., Germany and the U.K. all offered assurances to Gorbachev and Foreign Minister Eduard Shevardnadze that NATO would not expand toward the Russian borders. The documents make clear that the Western politicians meant no expansion to Eastern European countries, not just the East German territory.