President Donald Trump. Three words that were unthinkable to tens of millions of Americans — and much of the rest of the world — have now become the future of the United States.

Having confounded Republican elites in the primaries, Mr. Trump did the same to the Democrats in the general election, repeating the judo move of turning the weight of a complacent establishment against it. His victory is a humbling blow to the news media, the pollsters and the Clinton-dominated Democratic leadership.

The candidates appeared neck-in-neck in the popular vote, but Mr. Trump bested Hillary Clinton in the Electoral College.

So who is the man who will be the 45th president?

After a year and a half of erratic tweets and rambling speeches, we can’t be certain. We don’t know how Mr. Trump would carry out basic functions of the executive. We don’t know what financial conflicts he might have, since he never released his tax returns, breaking with 40 years of tradition in both parties. We don’t know if he has the capacity to focus on any issue and arrive at a rational conclusion. We don’t know if he has any idea what it means to control the largest nuclear arsenal in the world.

Here is what we do know: We know Mr. Trump is the most unprepared president-elect in modern history. We know that by words and actions, he has shown himself to be temperamentally unfit to lead a diverse nation of 320 million people. We know he has threatened to prosecute and jail his political opponents, and he has said he would curtail the freedom of the press. We know he lies without compunction.

He has said he intends to cut taxes for the wealthy and to withdraw the health care protection of the Affordable Care Act from tens of millions of Americans. He has insulted women and threatened Muslims and immigrants, and he has recruited as his allies a dark combination of racists, white supremacists and anti-Semites. Given the importance of the alt-right to Mr. Trump’s rise, it is perhaps time to drop the “alt.” David Duke celebrated Mr. Trump’s victory on Tuesday night, tweeting, “It’s time to TAKE AMERICA BACK!!!”

When Mr. Trump has looked beyond our borders, he has said that he would tear up the agreement to prevent Iran from building nuclear arms and that he would do away with the North American Free Trade Agreement. He has said that he would repudiate last December’s Paris agreement on climate change, thereby abandoning America’s leadership role in addressing the biggest long-term threat to humanity. He has also threatened to abandon NATO allies and start a trade war with China.

We know that, with Republicans controlling both houses of Congress, Mr. Trump would be able to restore a right-wing majority by filling the Supreme Court seat that Republican senators have held hostage for nine months.

Republicans will soon control every branch of the federal government, in addition to a majority of governorships and statehouses. There is no obvious check on Mr. Trump’s vengeful impulses. Other Republican leaders, including his running mate, Mike Pence, have largely made excuses for his most extreme behavior.

By challenging every norm of American politics, Mr. Trump upended first the Republican Party and now the Democratic Party, which attempted a Clinton restoration at a moment when the nation was impatient to escape the status quo. Misogyny and racism played their part in his rise, but so did a fierce and even heedless desire for change.

That change has now placed the United States on a precipice.

SOURCE: The New York Times Opinion