The US state department has warned that foreigners in the country who are found to be “praising, rationalising, or making light of” the killing of conservative activist Charlie Kirk may face punitive action, including visa consequences.

Deputy secretary of state Christopher Landau issued the warning in a post on X on Thursday morning, declaring: “Foreigners who glorify violence and hatred are not welcome visitors to our country.” He said he had instructed consular officials to “undertake appropriate action” against those identified on social media and invited users to flag posts for review.

Kirk, a rightwing provocateur and a close ally of Donald Trump, was shot and killed on Wednesday while speaking at Utah Valley University. His death has shocked the conservative movement and prompted tributes from across the Republican spectrum.

Crackdown on dissent and free speech

Landau’s comments reflect a broader pattern within the second Trump administration, which has stepped up scrutiny of foreign nationals for their political views. Immigration and Customs Enforcement (Ice) officers, traditionally focused on combating organised crime, have in recent months been tasked with investigating foreign students who express sympathy for the Palestinian cause or criticise Israel.

Officials have also been told to monitor social media for “anti-American” sentiments. New rules require international students to unlock their social media accounts before being granted educational or exchange visas.

A state department spokesperson defended the measures, saying: “This administration does not believe that the United States should grant visas to persons whose presence in our country does not align with US national security interests.”

Expansion of social media vetting

The extension of vetting to cover commentary on Kirk’s death would mark a significant widening of the administration’s approach. Diplomats are already required to flag any advocacy that could be interpreted as “support for foreign terrorists” or “unlawful antisemitic harassment or violence”. The new focus suggests that even remarks deemed flippant or critical could now affect an individual’s ability to enter or remain in the US.

Critics warn that such policies amount to a clampdown on free speech and dissenting opinion, disproportionately targeting international students and immigrants.

Trump blames “radical left” violence

President Trump paid tribute to Kirk from the Oval Office on Wednesday, calling him the “best of America” and accusing the “radical left” of fostering a climate of violence. He cited several recent incidents against conservatives but omitted killings and attacks on Democratic lawmakers earlier this year.

Meanwhile, MSNBC dismissed its senior political analyst Matthew Dowd after he suggested that Kirk’s combative rhetoric and record of Christian nationalist and anti-minority remarks may have contributed to the atmosphere in which he was killed.