Chart showing that disapproval of Nixon fell for both Democrats and Republicans roughly in step.

This means that as the story of impeachment develops, it will be understood differently across the network-based tribes of America. The correlation among conservatives and liberals alike that drove Nixon from the White House won’t be visible in 2020—because it won’t be there. Regardless of what happens, on one side, it will be justice delivered. On the other, justice denied.

That difference, in turn, will radically constrain the politicians who Americans have entrusted to render judgment on the president. The reality of Fox News Republicans will be persistently visible to red-state representatives. More idealistic, less inherently partisan senators like Ben Sasse might have a view of the “right” thing in their heart of hearts, but they will be forced to choose between what they know and what they know their very distinctive voting public believes. So far, few have faced that choice with courage.

Though the president was wrong to invoke it in this context, the Civil War may well have been the last time we suffered a media environment like this. Then, it was censorship laws that kept the truths of the North separated from the truths of the South. And though there was no polling, the ultimate support for the war, at least as manifested initially, demonstrated to each of those separated publics a depth of tribal commitment that was as profound, and tragic, as any in our history. That commitment, driven by those different realities, led America into the bloodiest war in its history.