When Rep. Chip Roy introduced the Mamdani Act this week, he may not have been thinking of McCarthyism, but he was making a direct reference to New York City Mayor Zohran Mamdani. The Measures Against Marxism’s Dangerous Adherents and Noxious Islamists (Mamdani) Act is an immigration proposal that would make noncitizens deportable and ineligible for naturalization, and even potentially subject to denaturalization over ties to or advocacy for socialism, communism, Marxism, Chinese communism, or “Islamic fundamentalism.” 

“Why do we continue to import people who hate us?” the Texas representative said in a press release. “Not just for the last six years, but for the last 60 years, our immigration system has been cynically used to disadvantage American workers’ competitiveness in favor of mass-importing the third world.

“By targeting the Red-Green Alliance, this legislation deploys new tools to fight back against the Marxist and Islamist advance that has devastated Europe and has now arrived on our doorstep, especially in my home state of Texas,” the statement continued.

The acronym references Mamdani, the 34-year-old democratic socialist who was sworn in as New York City’s mayor on Jan. 1 and became the city’s first Muslim mayor, first mayor of South Asian descent, and first mayor born in Africa. Mamdani was born in Kampala, Uganda, became a U.S. citizen in 2018, and campaigned on affordability proposals including free childcare, free bus service, and a rent freeze for rent-stabilized tenants.

The act would amend the Immigration and Nationality Act to add new deportability grounds for noncitizens who engage in advocacy, write or distribute written or electronic material supporting those ideologies, act on behalf of listed parties, or belong to affiliated organizations. Among the organizations are the Socialist Party of the United States, the Democratic Socialists of America, foreign or state-level socialist parties, successors or predecessors, and any “socialist-action” or “socialist-front” organization. Mamdani is a member of the Democratic Socialists of America, though he said he campaigns on his own platform and does not endorse all of the group’s goals.

Part of Roy’s proposal is already law. Current immigration law makes immigrants inadmissible if they are or have been members of or affiliated with the Communist Party or another totalitarian party.

Roy framed the proposal as a response to what he called the “Red-Green Alliance,” a term used by some conservatives to describe perceived cooperation between left-wing and Islamist movements. 

In March, Roy posted on X: “No more Muslims. No more criminals. No more Marxists. No more corporatists. #SaveTexas,” a message that drew backlash from critics who called it Islamophobic and anti-constitutional.

In October, Roy introduced the Preserving a Sharia-Free America Act, which would prevent naturalized Americans “who observe Sharia from entering the U.S. or from remaining in the country.” 

“America is facing an existential threat—the spread of Sharia Law. From Texas to every state in the union, instances of Sharia Law adherents have threatened the American way of life, seeking to replace our legal system and Constitution with an incompatible ideology that diminishes the rights of women, children, and individuals of different faiths,” the representative wrote in a press release at the time.

In November, he introduced the PAUSE Act, which would freeze nearly all immigration to the United States. “The problem isn’t just illegal immigration; it’s also legal immigration,” Roy wrote at that time.

Roy has had it out for the New York City mayor, describing Mamdani as “a self-proclaimed socialist, pro-Islamist, and naturalized U.S. citizen from Uganda,” in an op-ed. 

Neither Roy’s nor Mamdani’s office responded to Fortune’s request for comment.