correction: An earlier version of this op-ed incorrectly reported the annual number of H1-B visas. 65,000 foreign nationals may be issued a visa each year. An additional 20,000 H-1B visas are available to foreign nationals holding a master's or higher degree from U.S. universities. This version has been corrected.

A protester holds a sign at a rally in Denver last month after President Trump's decision to repeal a program protecting young immigrants from deportation. (Tatiana Flowers/AP)

From the Mayo Clinic website:

"Narcissistic personality disorder is a mental disorder in which people have an inflated sense of their own importance, a deep need for admiration and a lack of empathy for others. But behind this mask of ultraconfidence lies a fragile self-esteem that's vulnerable to the slightest criticism."

No, the entry is not illustrated with a photo of the president. But each day adds new pages to Trump's bulging textbook case. He is a farrago of grievance and grandiosity. What I want to highlight today, though, is the lack of empathy, because empathy is essential to constructive leadership. And we sure could use some of that.

Empathy is the ability to see through another's eyes, to understand and value the feelings of others. As the saying goes, it's the willingness to walk a mile in another's shoes. Empathy is not about feeling pity for someone else — that's sympathy. Rather, it is the recognition of common humanity. In an open society, empathy is the bedrock of civil discourse and durable policy, because these things are not possible without mutual respect.

Trump's lack of empathy reveals itself in moments large and small. In Puerto Rico, he bragged about his talent for hurricane relief while residents scrounged for food and water, waited endlessly for fuel, and faced weeks or months without electricity. And the same lack of presidential concern might explain the seemingly sorrowful eyes of Karen Pence, the vice president's wife, as she steeled herself to walk out of the Indianapolis Colts game last weekend in a Trumped-up political stunt. Togged in a blue-and-white Peyton Manning No. 18 jersey, the former first lady of Indiana clearly wished to pay honor to her home team's greatest star. Trump couldn't care less what she wanted.

For a moment, an ember of empathy seemed to glow in Trump's professed concern for the so-called dreamers. Brought to the country illegally as children, raised as true-blue Americans, these young adults may soon be subject to possible deportation to lands grown foreign to them. Trump promised to negotiate permanent protections "with heart." But when the White House released its list of demands in return, it was Trump's same old stew of scapegoating and xenophobia, poisonous to any possible compromise.

Nearly 700,000 dreamers consigned to anxiety, uncertainty and fear amounts to nothing in the president's calculations compared with his self-absorbed worry that his nativist choir might muffle their hosannas. And if by his posturing Trump kills any chance at progress on immigration, those won't be the only people affected. Hundreds of thousands of legal immigrants — holders of high-skilled H-1B work visas and their families — currently stand just one death or job loss away from the shadow of deportation. Their best hope for relief lies in the same immigration reform talks imperiled by Trump.

As a New Yorker, Trump surely understands the economic boost that newcomers represent. His home is an economic and cultural dynamo in large part because New York City attracts bright and ambitious young people from across the nation and around the world. Instead of pouring their ideas and energies into building up Birmingham or Boise or Boston, they add juice to the Big Apple. Healthy economies are magnets, not fortresses; their futures are bathed in the bright glow of headlights, not the red dim of taillights.

The H-1B program takes this same principle and applies it nationwide, allowing corporations, research institutions and schools to recruit up to 85,000 well-trained foreign-born workers each year. (That number should be higher.) After completing certain steps, visa holders can apply for green cards, which can lead to citizenship.

The wrench in the machinery is that no more than 7 percent of each year's allotment of green cards can go to H-1B workers from any one country. Thus, H-1B workers from the mega-populations of India and China are severely disadvantaged. By one estimate, engineers, doctors, scientists and other H-1B workers from India face delays of 50 to 350 years in seeking green cards, while workers from small countries — unaffected by the 7 percent cap — waltz right through.

Without that green card, highly desirable workers and their families face severe impediments to starting their own businesses and working their way toward citizenship. Indeed, spouses and children of H-1B holders are as vulnerable as dreamers should they lose their link to a visa through death, illness or layoff.

Earlier this year, Rep. Kevin Yoder (R-Kan.) discovered just how shaky this system has become when one of his constituents, an India-born engineer at the high-tech firm Garmin, was murdered at a bar by a stranger spewing anti-immigrant hate. The widow, whose immigration status depended on her slain husband's work visa, appealed to Yoder to help her gain permission to take the man's body to India for a family funeral. Without that intervention, she might have been barred from returning to the United States.

A humane immigration reform would include a Yoder-sponsored proposal to eliminate the cap that favors small countries, giving Asian immigrants a fair shot at green cards. Unfortunately, Trump's empathy deficit may kill any and all reforms.

If he can't empathize, though, perhaps he can see what any business owner ought to understand: An economy doesn't grow by walling out productive workers.

Read more from David Von Drehle's archive.