When the Supreme Court struck down President Trump’s birthright citizenship executive order in Trump v. Barbara, it settled for now in the courts who becomes a citizen at birth. It did not settle — and could not settle — whether American citizenship may be bought and sold.

It remains well within the power of Congress and the president to shut down the contracts, clinics, agencies, and visas that convert foreign money into American citizenship — without amending the Constitution or defying the court. Until the court revisits the issue, the political branches are solely responsible for overseeing the marketplace, and they have no excuse to delay.

Why buy a visa when you can commission a citizen?

If you doubt that such a marketplace exists, meet the Simpson triplets.

Nearly 20 months ago, Kyla Simpson of St. Augustine, Florida, gave birth to triplet boys as a gestational surrogate for an intended parent she had never met: a single man in China. He never came. Not during the boys’ two months in the NICU, not through the year and a half the Simpsons raised them, and not even when one of the triplets died of RSV.

When the man from China sent two strangers in a black SUV to collect the boys, Simpson refused. Then, she moved to terminate his parental rights, and he resurfaced with a lawyer and an emergency pickup order, which a Florida judge granted. The surviving twins, 20-month-old American citizens, now sit in state care while his attorneys obtain travel documents.

Why would a Chinese man pay hundreds of thousands of dollars for children he has never crossed an ocean to meet? Because he wasn’t buying children. He was buying American citizens.

A surrogate-born child of a foreign national receives a birth certificate, Social Security number, and passport at birth. When the child reaches age 21, he can petition for green cards for his parents and siblings, turning one commissioned pregnancy into chain migration for an entire family, at a fraction of the cost of the half-million-dollar EB-5 investor visa.

Why buy a visa when you can commission a citizen?

Birth tourism in overdrive

This citizenship-for-sale system has three serious dangers.

First, the burgeoning international surrogacy industry is a clear example of immigration fraud and abuse. For example, within days of President Trump signing the executive order on birthright citizenship, the agency Surrogate First issued workaround guidance for prospective parents, explaining that for international clients, “the certainty of their child obtaining U.S. citizenship at birth is a significant factor” in choosing America.

Likewise, Creative Family Connections advertised a “2-step birth certificate process” to guarantee citizenship for the children of foreign clients regardless of executive action. Prior to that, another agency pitched surrogacy as cheaper than the EB-5 investor visa.

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The co-founder of one California agency told NPR that dual nationality would be “a win-win situation for your children.” A fellow agent admitted many of her clients were “high-level Communist Party officials and celebrities” seeking American citizenship for their children.

Second, the international surrogacy industry is a national security threat that intensifies every year. Children with American passports who are raised under Chinese Communist Party rule can vote as adults in U.S. elections, join our military, work in sensitive research, and even run for president.

Beijing exploits every vulnerability American citizenship offers, whether the parents intend it or not. Why would it ignore this one?

Third, the industry is a child-welfare catastrophe. Authorities found 21 surrogate-born children in the home of a former CCP official tied to immigration fraud and smuggling — discovered only after an infant arrived at a hospital with severe head trauma in Arcadia, California. Chinese billionaire Xu Bo has reportedly commissioned 100 children and counting through American surrogates to build a personal dynasty.

According to data in the American Society for Reproductive Medicine’s own journal, surrogacy cycles commissioned by foreign intended parents surged 78% from 2014 to 2019, from 2,758 to 4,905 embryo transfers a year, with Chinese nationals the largest customer base at 41.7% — quadruple the next country.

More than 107 Chinese-owned surrogacy agencies operate in Southern California alone, many with Mandarin-only marketing and some listing offices in mainland China, where surrogacy is illegal. Indeed, international commercial surrogacy is merely the newest wing of a larger operation. Conventional birth tourism results in an estimated 50,000 to 100,000 annual U.S. births to Chinese nationals — a phenomenon that, according to investigative journalist Peter Schweizer, Chinese sources themselves describe as massive.

Since 2013, he estimates that more than one million “U.S. citizens” are being raised in China because their mothers came here to give birth.

Pulling up anchor

Yes, the Trump v. Barbara majority misread the 14th Amendment, whose author said it excluded “persons born in the United States who are foreigners, aliens.” A future court should revisit the issue, with the Simpson case as Exhibit A. In the meantime, however, there are concrete actions Congress and the executive branch can take to address birth tourism.

Close the state loophole with federal law. Earlier this year, Florida became the first state to prohibit surrogacy contracts with foreign nationals from adversarial nations, including China, Russia, Iran, and others. But the law does not stop Florida citizens from working with a California-based agency.

We need federal action to shut this market down. As Sen. Rick Scott (R-Fla.) proposed via the SAFE Kids Act and Rep. Scott Perry (R-Penn.) introduced via the Preventing International Surrogacy Exploitation Act, Congress should ban international commercial surrogacy outright by prohibiting foreign nationals from contracting with American surrogates or agencies.

Notably, the vast majority of developed nations — aside from the United States and Ukraine — already have a law like this in place.

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Cut off the travel and count the trade. Congress and the State Department should deny visas to anyone traveling to the U.S. to commission or collect a surrogate-born child. They should also mandate federal reporting, through the CDC or another agency, of every commercial surrogacy contract and resulting live birth, including the client’s nationality.

There is no reason to regulate the export of technology more carefully than the export of our own citizens.

Make the buyer, not the baby, pay the price. Heritage Foundation Vice President Roger Severino has proposed the boldest remedy. Vice President JD Vance has already endorsed Severino’s plan to end birth tourism citizenship in U.S. territories, which China has exploited.

Every solution so far has focused on the “anchor.” Severino’s plan, by contrast, targets the “boat.” Under existing law, the president has broad authority to bar any class of foreign nationals whose entry he deems detrimental to U.S. interests.

He should use that power to give every foreign national without permanent residency who has a child on U.S. soil a simple choice: Relinquish the child’s American citizenship, or never legally set foot in the United States again.

This doesn’t remove citizenship from the children. But it does mean that the parents who refuse would become permanently ineligible for any visa, asylum, refugee status, or temporary protected status; any lottery or family-based entry; or any future path to residency or citizenship, including through marriage to an American.

The Supreme Court says these children are citizens. Very well — then act like it.

American citizens should not be purchased for export, warehoused unclaimed, or shipped beyond the reach of American courts. The 14th Amendment was written so that no one born on American soil could be bought or sold. It’s time to extend that same protection to children born via international commercial surrogacy schemes.

Editor’s note: A version of this article appeared originally at the American Mind.