This post was updated April 3rd at 9:36 p.m.

Editor’s note: The views expressed in this op-ed are those of the author’s alone and are not the official positions of UCLA, the campus, or any academic unit, department or program at UCLA.

The recent arrest of Tufts University doctoral student Rumeysa Ozturk should shock and worry everyone at UCLA.

She was studying in the U.S. on a valid visa and has not been charged with a crime. By the government’s own admission, she is in prison today for her speech – for what she wrote in an op-ed published by the student newspaper a year earlier.

Ozturk is just one of many international students currently being pursued by President Donald Trump’s administration, which has promised to arrest many more soon.

Many are bracing for the arrests to begin here at UCLA. This is part of a broader campaign by Trump to intimidate and control institutions of higher education.

No matter who you are or what you believe, this is an attack on all of us.

Our constitution protects freedom of speech to ensure we all benefit from the free and open exchange of ideas. For this reason, the courts have held that the First Amendment applies to citizens, non-citizens and even corporations. When speech is stifled, this doesn’t just affect the speaker, it also infringes on your right to hear what others have to say.

An environment of fear and self-censorship runs directly counter to UCLA’s stated commitment to free speech. How can UCLA remain a globally respected university when international scholars and faculty are afraid to speak?

How can we feel comfortable discussing anything controversial on campus, including transgender rights, the war in Ukraine, climate change, vaccines and tariffs?

The list of topics that will be off limits will only grow and grow along with Trump’s enemies. Unfortunately, those of us who can speak, including university leadership at UCLA and around the country, have been failing to speak out against this incredible attack on our freedom.

They are afraid that saying anything that would displease Trump could put university funding at risk or open them up to federal lawsuits and investigations. But capitulating to Trump’s threats is a losing strategy.

No matter what UCLA leadership says or does, Trump will use every tool at his disposal to silence critics and gain full control of UCLA.

As a case in point, as I was drafting this letter, the Department of Justice announced investigations into UCLA’s admissions process.

These are no ordinary times. Trump’s arrest of Ozturk is a clear and present danger to hundreds of students and faculty right here at UCLA.

It poisons the educational environment on campus and infringes on our mission as an institution.

This demands an immediate, forceful and unified response from UC leadership, including UC President Michael Drake and UCLA Chancellor Julio Frenk. In moments like these, we need to stand together to defend our rights.

Silence is not an option.

Andy Kleinhesselink is an ecologist and the managing director of Sage Hill at UCLA.