Paul Whelan was left behind in Brittney Griner swap — here's why it's so hard to get him out of Russia

This week, President Joe Biden managed to broker a prisoner swap with Russia, allowing the release of basketball star Brittney Griner in exchange for Russia being handed Viktor Bout, an arms trafficker known as the "merchant of death." Notably absent from the swap, however, was Paul Whelan, a former U.S. Marine who has been stuck in Russian prison for years on dubious espionage charges.

On Thursday's edition of MSNBC's "Morning Joe," reporter Andrea Mitchell detailed the key reason why it has been so hard for the Biden administration to broker Whelan's freedom.

"So the swap was done, she is on her way home and the president is about to announce that," said Mitchell. "The fact is that the Paul Whelan news is dismaying. His parents were very concerned because he had gotten out of touch. And then I learned last sunday, and David Whelan confirmed this with us on Monday, that he was actually taken from the prison to the prison hospital even though he wasn't sick, with no explanation, on Thanksgiving Day, so that he could not call home."

Whelan, Mitchell continued, "deserves better from this government and I encourage Biden to get his return using all tools available ... but I think that it is going to be difficult for the administration and they know this."

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The big problem with Whelan, Mitchell said, is the specific nature of the espionage charges Russia convicted him on, which are much more serious than Griner's charges for drug use.

"The Russians were demanding that a Russian spy be turned over in addition to Viktor Bout, the notorious arms dealer, and the U.S. position is they don't have any Russian spies in captivity to turn over," said Mitchell. "Initially, as you may recall, the Russians were demanding that a man, a spy in German captivity — assassin, actually — had to be turned over, and U.S. said, we can't ask the Germans to turn someone over. So they said they had nothing to offer and the Russians were demanding that if Whelan was going to get out, they had to get someone labeled a spy. And Whelan is not a spy according to him, his family, and the U.S. government. So, bittersweet moment, but certainly great news for Brittney Griner and her family and fans."

Watch video below or at this link.