In the late 1950s, my parents tried to buy land in northern New Jersey on which to build a home. But no one would sell to them. A real estate agent said it was because they were Chinese.

It was a time when, throughout the United States, residential segregation was common, supported by mortgage lending practices and often written into real estate deeds with racial covenants that forbade the sale of a home to Black people, Jews and Asians. In the late 19th and early 20th centuries, Western states passed alien land laws, which prohibited Asian immigrants from buying or leasing agricultural property. The rationale for these restrictions was to prevent Asians, envisioned as an alien invasion, from taking over the United States.

Now new laws are targeting Chinese people from owning property again. Last month, during their third debate, G.O.P. presidential hopefuls made proposals ranging from building up America’s nuclear submarine force to forbidding Chinese nationals to buy land in the United States. Gov. Ron DeSantis boasted, “I banned China from buying land in the state of Florida.”

Florida is just one of several states that are passing laws prohibiting the sale of residential, business or agricultural property to Chinese nationals, Chinese-owned companies or the Chinese government near military facilities, airports and other critical infrastructure. In many states, restrictions also apply to those from Iran, Russia, North Korea and other countries of concern. To date, at least 15 states have enacted laws restricting foreign land ownership, including Florida, Virginia, Alabama and Montana; about 20 other states have bills pending. Some have been introduced at the federal level.

The rationale behind today’s version of the alien land laws is familiar: People and companies of foreign adversaries with property in the United States pose a threat to national security. Proponents of these laws argue that our adversaries might spy on military bases, endanger our infrastructure or even threaten the nation’s food supply.

In May, when Mr. DeSantis lauded Florida’s land bill (which offered exemptions for some residential property) as a protection from the Chinese Communist Party, he invited the public to consider Chinese people (and by association, all Asians) to be Americans’ racial, geopolitical and ideological enemies. The notion that ethnic Chinese people in the United States — including U.S.-born and naturalized citizens — can never be true Americans because they are innately loyal to China has been baked into U.S. politics for over 100 years.

Since the late 19th century, the yellow peril fear mongering fueled racist legislation throughout the West against Chinese and other Asian people. In addition to the land laws, laws excluded Asians from testifying in court against white people, from marrying white people, from attending schools with white children and from holding professional and commercial licenses. The Supreme Court upheld the Chinese Exclusion Act of 1882, the national policy barring Chinese people from immigration and citizenship, on grounds that they were a racial danger and a threat to national security, even absent hostilities between the United States and China. The anti-Chinese and anti-Asian laws were apiece with the reversal of Civil War gains for African Americans and the advent of Jim Crow in the South. The triumph of white supremacy over democracy, led by the South and the West, endured well into the 20th century.

The new land laws are the latest in a wave of anti-Chinese measures. During his administration, Donald Trump, blaming the Covid pandemic on China and Chinese people, unleashed a firestorm of racist harassment and assaults against Asian Americans. Under 2018’s China Initiative, academic scientists at American universities who were Chinese nationals or U.S. citizens of Chinese descent were harassed and persecuted. Mr. Trump also threatened a tariff war against China, establishing import restrictions that remain in place. Today, President Biden seems to maintain the Trump administration’s designation of China as a strategic adversary and has increased trade restrictions against the nation.

It’s hard to oppose the purported justification for these measures: national security. After all, we don’t want the enemy spying on our bases or blowing up airports. But how credible is the threat? Foreign nationals own about 3 percent of privately held agricultural property in the United States, and Chinese people own less than 1 percent of that, according to the Department of Agriculture. The potential threat from Chinese-owned farms is wildly exaggerated. In other cases the Chinese threat is fabricated: Chinese people were victims of the coronavirus, not its cause.

The China Initiative, which might have started with a legitimate concern over intellectual property theft, soon spun out of control. It became the basis for the racial profiling of Chinese and Chinese American professors at research universities. According to the cases analyzed by researchers at M.I.T., none of those brought against academic scientists under the China Initiative revealed evidence of economic espionage or other intellectual property theft. The program was disbanded last year. Still, 72 percent of Chinese and Chinese American scientists did not feel safe in their jobs, according to a survey conducted by a team at Princeton, M.I.T. and Harvard in 2021 and 2022. A reverse brain drain from the United States of ethnic Chinese scientists, coupled with a drop in the number of Chinese students applying to American universities, threatens to deprive the United States of scientific talent. Portraying China as the enemy is the politics du jour in America. It plays on anxieties over China’s rise as a global economic power and has proved to be politically strategic. However, it has grave consequences.

This summer, the Biden administration dialed back some of its bluster. Treasury Secretary Janet Yellen called for “derisking,” not “decoupling,” trade relations with China; last month, Mr. Biden met with President Xi Jinping in California in a step toward stabilizing relations. While lowering the temperature is welcome, it is not enough. The administration should stop seeing trade with China solely through the prism of national security. As long as that linkage persists, Chinese and other Asian Americans will continue to be on the receiving end of racist harassment, violence and discrimination.

After the United States entered World War II, the government rounded up some 120,000 Japanese Americans mostly living on the Pacific Coast and detained them in camps — even though, per military intelligence, they were no threat to national security. The United States did not issue a formal apology for the internment until 1988. And although the Supreme Court weakened racial covenants in real estate and the alien land laws in 1948, one wonders how the current spate of alien land laws would fare before the current court.

My parents were physicians who emigrated from China after World War II. During the 1950s, my dad served in the U.S. Army and became a naturalized citizen. My parents wanted their family to live the American dream in the suburbs. They eventually bought a house in a mixed-race township. They benefited from gains of the civil rights era, won by African Americans and redounded to other people of color. My parents were successful in their careers, though they were not strangers to discrimination. Were my parents alive today, I know that they would be worried about the United States’ China policies and the bull’s-eye it plants on our backs.

Mae Ngai is a professor of history and Asian American Studies at Columbia University. She is the author of “The Chinese Question: The Gold Rushes and Global Politics.”

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