One part of the explanation is the structural situation of the news media. As newspapers die off, their place in the American consciousness is taken by social networks of both the formal and informal variety. Thanks to Facebook and Twitter, these days we read only that which confirms our biases. Once upon a time, perhaps, the Washington Post could single-handedly bring down a president, but those days have passed.But there’s also a second reason, one that is even more fundamental. The truth is that the unanimous anti-Trumpness of the respectable press is just one facet of a larger homogeneity. As it happens, the surviving press in this country is unanimous about all sorts of things.