President Trump waves as he walks to Marine One on the South Lawn of the White House in September. (Alex Brandon/AP)
Contributing opinion writer

When Donald Trump’s political autopsy is written, the exact time of death will be uncertain, but it will be fixed sometime around the 2018 midterm elections when enough of the country decided that it had had enough.

Cause of death, somewhat unexpectedly, will not be a single event, not his racist reaction to Charlottesville, or his siding with Vladimir Putin over his own intelligence branches, or his obstruction of justice, or his threatening to cut off federal aid for the burned-out citizens of California’s fires, or any of his other misdeeds, but rather the accumulation of all of them. In medical terminology, the cause will be “death by misadventure.” This accident of democracy will have politically expired, due to “deliberate assumption of unreasonable risk by the victim.” In other words, he came too close to the edge too many times and finally fell.

How can we be so certain that Trump’s political days are numbered? First, now we can see more clearly that the blue tide kept rising as many of the closest races, especially for the House, flipped to the Democrats as the final votes were counted. Democrats are now set to gain nearly 40 seats in the House — their biggest gain in decades.

Second, we have the smart analysis this past weekend from Democratic pollster Stanley B. Greenberg that the shift away from Trump in 2018 was more profound than many initially believed. In fact, Greenberg makes a strong case that the election was “transformative” with Trump losing support, not only with suburban, college-educated women, but all women. And Democrats gained ground in other areas, too, including working-class men and in rural areas.

The likelihood that Democrats will maintain these gains though the 2020 election is very promising. Unlike many incumbent presidents who have retooled their approach in the face of stinging midterm rebukes, Trump has signaled he’s sticking with his risky behavior. The attack tweets, the latest puerile joke about a congressman’s name and indefensible behaviors, such as believing a foreign power instead of the CIA about the murder of Jamal Khashoggi, will continue.

Trump will not pass from our politics suddenly from a single dramatic cause, but rather from the accumulation of self-inflicted wounds. It has taken much longer and done more damage than many hoped, but the end of Trump is finally in sight.