Some say that we aren’t in a constitutional crisis. The proponents of this point of view argue that the courts have yet to register their opinion on Trump’s refusal to cooperate with Congressional oversight. And in the event that they rule against the administration, we don’t know what the White House would do. Would it comply with the ruling? Or would he defy it? And if it did then what?
I can’t think of a more narrow, sterile, and formal way to determine whether we are in a constitutional crisis. Any answer to this question has to employ a much wider lens. When we do, we observe that in the wake of the Mueller report, Trump and his coalition of supporters in and outside of government have become more emboldened, not chastened. Their obstruction and lawlessness continue unabated. They openly sport an “enemies” list. The finger of executive privilege meets every request from Congress. Nixon’s transgressions look like small potatoes in some ways. Moreover, the earlier push back, mild as it was, from the National Security State and the Republican Party against the Trump administration has largely disappeared. Worse still, Trump has his guys, or better hacks, at Justice, State, and Defense now, not to mention John Bolton as his National Security advisor and his new appointees on the Supreme Court. 
Finally, this right wing, white nationalist authoritarian political bloc, headed by this reckless and narcissistic president, is executing at this very moment a broad scale, offensive at home and internationally to make the world bend, and break if necessary, to its dictates. Such an offensive can only happen by further laying waste to constitutional and democratic norms and institutions as well as people’s lives, economic well being, and rights. The crisis of this moment then is political as well as constitutional, immediate as well as general.
While next year’s elections can’t come soon enough, it is imperative that the leaders of the diverse coalition resisting Trump finds ways at this moment to practically engage and unite the majority of the people that oppose this exceedingly dangerous turn in our country’s politics. Later could well be too late!