Protesters clashed with police in London’s Trafalgar Square on Monday at a demonstration in solidarity with Palestine Action. The crowd moved towards police when officers tried to detain someone, while protesters chanted “let them go”.

It would be illegal for anyone to promote Palestine Action or be a member. Those who breach the ban could face up to 14 years in prison.

Activists from the group broke into a Royal Air Force (RAF) base in central England last week and claimed to have damaged two military aircraft to protest against the UK government’s support for Israel’s war on Gaza.

There has been condemnation of the government’s move on Monday. Labour Party MP Apsana Begum said: “Proscribing Palestine Action as ‘terrorists’ while continuing to send arms to a state that is committing the gravest of crimes against humanity in Gaza is not just unjustifiable, it is chilling. The ongoing crackdown on the right to protest is a threat to us all.”

Weekly protests in the UK have drawn tens of thousands of people opposed to Israel’s war on Gaza and its besieged and bombarded population, as well as Britain’s supply of weapons to the Israeli military, which the government says it has suspended but still continues.

For perspective, there are 220 Democrats in the House of Representatives, all of whom have been unabashedly vocal in their criticism of the Trump administration’s actions on a near-daily basis.

There are 45 Democrats in the Senate.

But only a select number of self-styled progressives including Ilhan Omar, Ayanna Pressley, Summer Lee, and Al Green – the man thrown out of President Donald Trump's State of the Union speech last week – were willing to add their names to language that leaves no room for interpretation.

“We are horrified by the recent illegal abduction and now indefinite detention of Mahmoud Khalil – a US legal permanent resident – by Department of Homeland Security (DHS) agents, and we unequivocally demand his immediate release from DHS custody,” the letter said.

“Khalil's arrest is an act of anti-Palestinian racism intended to silence the Palestine solidarity movement in this country,” it read. “He is a political prisoner.”

Among those notably absent from the document was Alexandria Ocasio-Cortez, otherwise known as AOC. She grew her brand as a member of the so-called "Squad" of progressive women in the House of Representatives but came under fire throughout Israel’s war on Gaza as she adopted what many saw as a more establishment-friendly tone within the Democratic Party.

After a social media firestorm, AOC’s chief of staff said she would have definitely signed the letter if it wasn’t too late, and that she was simply “waiting on a detail before signing”.

“Unfortunately, the letter was closed before that detail was confirmed,” he said on X.

“There are potentially logistical reasons for that, or just internal congressional process reasons for that,” one Democratic strategist working on Palestinian advocacy in Congress told Middle East Eye.

“I do think more lawmakers have spoken out than signed that letter.”

By the end of the day, it was revealed that AOC had signed a similar letter along with fellow New York Democrats serving at the local level.

Columbia University is located in New York City.