In late September, one of the world’s most intractable conflicts ended suddenly and brutally when Azerbaijan seized the enclave of Nagorno-Karabakh and tens of thousands of ethnic Armenians fled their homes. Andrew Higgins, the New York Times bureau chief for East and Central Europe, explains how the conflict started, why it lasted for more than 30 years, and what its end can tell us about the nature of seemingly unsolvable disputes. Guest: Andrew Higgins, the East and Central Europe bureau chief for The New York Times.