The nicest way to put it is that Michael Flynn is a complex character.
The truth is that he is a chameleon always looking for his next mark.
We can't be sure exactly why Obama fired him, but it does not seem to have been over a sincere difference of opinion regarding America's national interest.
A lot of people disagreed with Obama about America's national interest. Some of them thought we should get closer to Turkey, perhaps. Some of them thought we should get closer to Russia, even though Russia was invading Crimea. Yet no sincere person believed all three things. If you pick a fight to get Obama to fire you, then write a book about how out of touch Obama is, but then take money from both Russia and from Turkey, you're not a sincere American patriot, with a difference of opinion, no, you're just after fame and money. Everyone in the Obama administration who dealt with Flynn knew this. Pence knew this. The lie that Flynn told Pence probably concerned one of these things. Trump knew this also at one time. He is just conveniently forgetting, to get an anti-Biden story into the news cycle.

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