Can Donald Trump govern this country?

He starts with several large advantages: the fervent support of white, working-class voters and the Republican control of Congress. In his victory speech, he struck generous themes of unity, vowing “to every citizen of our land that I will be president for all of Americans.”

But Trump is going to learn very quickly that being president is far tougher than running for president. Even with his allies controlling Capitol Hill, he’s going to face enormous obstacles that will make his job extremely difficult from Day 1.

Start with the way the campaign played out. Trump complained repeatedly that th...