Analysis: Russians were warned not to violate Turkish airpace

The head of NATO is calling for calm after Turkey shot down a Russian fighter jet, killing at least one of the two pilots. It is the first time the North Atlantic Alliance has downed a Russian or Soviet military plane since the Cold War days of the 1950s.

Global conflict feared after downing of Russian jet

Russian President Putin insists the plane was in Syrian airspace, but the Turks put out a radar image which they say shows the path the plane took as it briefly entered Turkey. After 10 warnings without a response, a Turkish fighter jet shot it down.

In the video above, Scott Pelley discusses the ramifications of the shoot down with Ambassador Nick Burns. Burns is a career American diplomat, former National Security Council Director for Russian affairs and former U.S. Representative to NATO. He now teaches diplomacy at Harvard.

Ambassador Nicholas Burns CBS News

"Every nation has a right to protect its own borders," said Burns. "It was a gross violation of international law for the Russians to even fly close to that border, but to cross it? That's a red line that can't be crossed," he continued.

Ambassador Burns also said deescalation the situation is important in order to continue the united fight against ISIS.