“Don’t normalize this” has become a kind of rallying cry during President Trump’s first year in office -- a reminder to not get too acclimated to Trump’s norm-breaking and erratic behavior.

But the real danger of the Trump presidency might have less to do with Trump’s abnormality and more to do with how “normal” he makes other Republicans look by comparison.

There’s a concept in political theory developed by Joseph P. Overton which suggests that there’s a “window” of acceptable ideas and policy proposals in public discourse. Everything inside the window is normal and expected, while everything outside the window is radical, ridiculous, or unthinkable. And Overton argued that the easiest way to move that window was to force people to consider ideas at the extremes, as far away from the window as possible. Because forcing people to consider an unthinkable idea, even if they rejected it, would make all less extreme ideas seem acceptable by comparison -- it would move the “window” slowly in that direction.

That “Overton Window” concept is helpful for explaining how media coverage of Trump has been warped during his first year in office. Trump’s presidency has forced news networks to grapple with conspiracy theories, right-wing trolls, and dishonest government spokespeople -- making them a regular fixture of our national political debates. And that grappling has moved the Overton Window in ways that will warp our politics long after Trump’s presidency comes to an end.

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