Democratic impeachment dreams will inevitably collide with a Constitution that makes removal of a president all but impossible. With the current Senate line-up, Democrats would need to persuade 20 Republicans to join all 47 of them for the two-thirds vote to drive Trump from office.

In 232 years of Constitutional history, no US Senator—not even one—has ever voted to remove a president of his or her own party. What happened to Richard Nixon in 1974? The Watergate crisis climaxed in the midst of a midterm election campaign; a campaign in which the GOP ultimately lost 48 House seats and 5 in the Senate.

In a desperate bid to mitigate looming disaster, Senate leaders begged Nixon to resign. For the sake of his party and his country, he did so. In Trump’s case, elections are nearly two years away and, barring unforeseen, catastrophic revelations, his resignation is inconceivable.