Story highlights Trump's second meeting with Putin on the sidelines of the G20 summit should raise alarm bells, David Axelrod writes

The specter of an inexperienced President meeting with a seasoned leader defies every rule of diplomacy and good sense, he writes

David Axelrod is a CNN commentator and host of the podcast "The Axe Files," now a regularly featured show on CNN. He was senior adviser to President Barack Obama and chief strategist for the 2008 and 2012 Obama campaigns. The opinions expressed in this commentary are his.

(CNN) President Barack Obama was running behind.

In Moscow for bilateral talks with Russian President Dimitri Medvedev in the summer of 2009, Obama took a meeting with Prime Minister Vladimir Putin, widely understood to be the power behind the throne. Now, the meeting with Putin was going well beyond the allotted hour, and the President was late for an appointment with former Soviet President Mikhail Gorbachev.

As a senior adviser, I was asked to sit in with Gorbachev until Obama arrived. During our 45 minutes of conversation, the aging Soviet leader, still spry at 78, mused about his meetings with President Ronald Reagan that led to historic breakthroughs in US-Soviet relations.

"He would sometimes go off on tangents and (Secretary of State) George Schultz, who was sitting next to him, would gently place his hand on Reagan's. And Reagan would just stop," Gorbachev told me.

I thought of this story when we learned that President Donald Trump had had an unreported conversation with Putin at the recent G20 meeting in Hamburg -- with no aides present and only Putin's translator as a party to the chat.

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