Over the past few decades, both Democrats and Republicans in Congress have moved away from the center. But the Republican Party has moved toward the extreme much more quickly — a trend that political scientists’ call “asymmetrical polarization.”

That asymmetry poses a major obstacle in American politics. As Republicans have become more ideological, they’ve also become less willing to work with Democrats: filibustering Democratic legislation, refusing to consider Democratic appointees, and even shutting down the government in order to force Democrats to give in to their demands.

Democrats have responded in turn, becoming more obstructionist as Republican demands become more extreme.

And that’s made it really easy for media outlets to blame “both sides” for political gridlock. As political scientists Thomas Mann and Norm Ornstein explain in their book It’s Even Worse Than It Looks, journalists feel a pressure to remain neutral when covering big political fights. So politics coverage has been dominated by the myth that both parties are equally to blame for the gridlock in Washington.

But they’re not. And the only way to stop Republicans in Congress from continuing their drift toward the extreme is to be brutally honest about who’s responsible for breaking our politics.

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