On our new Foreign Policy feed, we wrote an open letter to Vice President Pence. It begins:

Dear Vice President Mike Pence:

A betting man might place odds that, sometime in the next three and a half years, and maybe a lot sooner than that, you will become president of the United States. The present situation in the White House is unsustainable. The time has come for you to consider the possibility that, as a result, it will not be sustained and that you, as a consequence, have a date with history at some point on your calendar.

True, your boss’s impeachment and removal remains a low-probability event. A Republican-controlled Congress has already allowed the president to cross thresholds that would surely have led to the removal of prior commanders-in-chief. While this may reflect little more than base political calculations, impeachment is an exceptionally grave act before which one should naturally hesitate. The preeminent legal scholar Charles Black opened his book on impeachment by arguing that “[e]veryone must shrink from this most drastic of measures.” Writing in Lawfare, Jane Chong notes: “Acknowledging his own status as a longtime political opponent of then-President Richard Nixon, Black nonetheless expresses ‘a very strong sense of the dreadfulness of the step of removal.’ Impeachment must be treated like high-risk surgery, he insists, ‘to be resorted to only when the rightness of diagnosis and treatment is sure.’” So it may take time, and your appointment with history may never come.

But consider, at this stage, the odds that President Trump will be removed from office early are certainly not lower than the odds of his election in the first instance. Only last week, a Republican senator spoke the words: “the beginning of the end of the Trump presidency.” Your boss is completely out of control. You know this, probably better than we do. You know that he is incapable of controlling his behavior and could lash out at any moment in a fashion that could be ruinous. You know that’s true even if there’s nothing to all those Russia allegations. And you know that all those denials—including the ones to your face—have proved false. You know, in other words, that it could happen. And if it does, you will face the monumental task of leading a fractured country forward out of the wreckage. The time to begin preparing for that moment is now.