Comment: "Bannon damaged his standing by giving an interview to the liberal American Prospect this week in which he was seen to be undercutting Trump's position on North Korea."

Missing here is the OTHER comment made by Bannon that undercut some of Trump's base support.  Bannon called Neo-Nazis and white supremacists "clowns" in the same interview, I believe. THAT might have been the tipping point.  

About Bannon blithely stating he'll go back to Breibart?  Hmm, maybe.  Perhaps he won't be welcome there, either.  Not for his ideological beliefs, necessarily, but simply because, in his absence, the website's management has "moved on" so to speak, and he's simply not wanted on the voyage. What an irony that would be.