“Give me your tired, your poor,

Your huddled masses yearning to breathe free…”

— Emma Lazarus, poem at the base of the Statue of Liberty installed in 1903.

“I want to be clear to folks in this region who are thinking about making that dangerous trek to the United States-Mexico border: Do not come. Do not come. … if you come to our border, you will be turned back.”

— Vice President Kamala Harris, remarks in joint press conference with President Giammattei of Guatemala in Guatemala City, June 7.

A Democratic congresswoman from New York City, Alexandria Ocasio-Cortez, publicly criticized the comment by Ms. Harris. “This is disappointing to see,” Ms. Ocasio-Cortez tweeted, observing, “seeking asylum at any US border is a 100% legal method of arrival.”

I don’t often agree with Ms. Ocasio-Cortez, but I too found the vice president’s comment disappointing.

As policy, it doesn’t break new ground. President Biden, in a March 16 interview with ABC News, said, “I can say quite clearly: Don’t come …. Don’t leave your town or city or community.”

As a statement of American aspirations, though, it falls flat. Imagine if in 1958 Vice President Nixon had appeared in India and announced to Shyamala Gopalan: “Do not come. Do not come.” Such a comment by Nixon might have discouraged Gopalan from making the journey as a young student to the University of California, Berkeley — and without that, Gopalan’s daughter Kamala Harris might never have been born an American.

Nor is Ms. Harris the only child-of-an-immigrant in the news these days.

Amazon executive chairman Jeff Bezos, the world’s richest person according to the Bloomberg Billionaires Index, is planning a pioneering private trip into space on July 20. His father, Mike Bezos, came to America from Cuba at age 16 in 1962 — by himself, speaking almost no English and, according to a CNBC account, wearing a jacket “hand-stitched from cleaning rags.” Imagine if Vice President Johnson had shown up in Cuba to tell Mike Bezos: “don’t come.”

This past Sunday’s New York Times Magazine was largely devoted to an essay by my former colleague Jonathan Mahler about the future of New York City, including the City University of New York. Mahler concludes, “Decades ago, when CUNY was a redoubt for newly arriving Jewish New Yorkers, it produced no fewer than 13 Nobel Prize winners. What might be possible now, if instead of giving CUNY just enough money to survive, we gave it twice what it needed?” What led to the 13 Nobel laureates, though, wasn’t so much lavish government funding but immigrant energy.

On Tuesday, the Senate Judiciary Committee is scheduled to hear the American Dream and Promise Act of 2021, which passed the House in March on a 228 to 197 vote. It would make things easier for illegal immigrants already in America, but would leave the overall entry system mostly unchanged. A modestly broader, though not comprehensive, immigration law overhaul, the United States Citizenship Act, has been languishing in both the House and Senate.

President Biden has given mixed signals on immigration. Initially, he left unchanged Trump-era refugee ceilings. Then, after an outcry from advocacy groups, he said he would raise the refugee admission levels. His legislative agenda has focused on Covid-19 relief and “infrastructure,” not increasing the flow of legal immigration. Some suspect that Democrats cynically leave the immigration issue largely unresolved so that they can bring it out periodically during campaign seasons as a political weapon to wield against Republicans.

Politicians have different constraints than poets. Mr. Biden and Ms. Harris may figure the last thing they need dominating the news is a caravan of Latin Americans headed for the border. The Biden-Trump expansion of the welfare state — an expanded tax credit, extended pandemic unemployment, “stimulus” checks—creates a magnet. It’s often said that a country can have an open border or a generous welfare state, but not both simultaneously.

America’s success, though, owes to generations who risked the journey here, lured not by a handout but by this land’s freedom and by the rewards it offers for hard work. If our ancestors had all heeded the injunction “do not come,” here’d be a lot fewer Americans celebrating on July 4. Maybe the next time Ms. Harris travels abroad she can experiment with something more hopeful, closer to “If you want to live by our Constitution and be part of the world’s greatest story of freedom and growth, please consider joining us. We would welcome, and benefit from, your talent and energy.”