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Two quick thoughts on the Steve Bannon-President Trump feud:

One, it’s a sign of the apparent seriousness of the Russia investigation for Trump’s family and inner circle. The insults got the attention, but the more significant part of Bannon’s remarks may be the “logical, cold-eyed recognition” that prosecutors are building a powerful case, notes Errol Louis at CNN.

Two, the feud is a reminder that Bannon has failed to accomplish his biggest ambition: Expanding the Republican coalition to include many more middle-class and working-class voters. “Steve Bannon had a chance to be a genuinely significant figure in American politics and he blew it,” my colleague Ross Douthat wrote on Twitter.

Democracy. Later this month, an alarmingly titled book, “How Democracies Die,” written by two political scientists, will be published. It is, as the book’s promotional material states, “a bracing, revelatory look at the demise of liberal democracies around the world — and a road map for rescuing our own.”