CHICAGO – Summer Pappachen and 200 other activist students at Northwestern University had just set up more than two dozen tents and tarps on the picturesque university lawn. The mood in the morning was calm. Students brought Palestinian flags and drums to play for passing cars honking support.

Then the cops showed up to shut them down.

“We thought it’s Northwestern University, they have a liberal reputation to uphold, but they came within minutes,” Pappachen said of Thursday's confrontation. Campus police began removing tents, but left after about 100 protesters linked arms and formed a barricade.

Papachen and thousands of other student protesters around the nation have seen an unexpected side of their colleges: what they consider a militarized response to basic civil rights and free speech.

From California to New York, from Texas to Illinois, hundreds of students have been arrested after college presidents called police - some in riot gear and some carrying tear gas - to remove their own students from encampments on campus quads. Some question whether authorities are over-reacting; others question the priorities of academic leaders who sic the police on them.

At Northwestern, Pappachen, a 25-year-old grad student, said organizers quickly conferred with protesters at Columbia University in New York, an epicenter of growing student dissent against the Israel-Hamas war, on how to handle police if they returned.

“We’ll see if they’re interested in arresting their own students and employees,” Pappachen said. By nightfall, more than 500 protesters had gathered on the lawn, and she was telling students through a bullhorn about what to do if they were arrested.

Polarizing question of free speech vs. safety

The student-made tent cities that have been at the heart of the Israel-Hamas protest conflicts have sprouted up at several universities, most notably Columbia. For college presidents, the encampments are often seen as an intimidating presence and interruption of life on campus.

"I fully support the importance of free speech, respect the right to demonstrate, and recognize that many of the protestors have gathered peacefully," Columbia University President Minouche Shafik said in an email sent this week to all students and faculty that was obtained by USA TODAY. "However, the encampment raises serious safety concerns, disrupts campus life, and has created a tense and at times hostile environment for many members of our community. It is essential that we move forward with a plan to dismantle it."

At UCLA, Students for Justice in Palestine set up an encampment Thursday on Royce Quad. "We are not leaving until our demands are met," the group said in an Instagram post. Also in Los Angeles, the University of Southern California declared its campus closed and asked the L.A. Police Department to clear a demonstration after it arrested 94 people linked to a protest Wednesday.

Protest organizers say the police responses across the nation are overzealous. At the University of Texas at Austin on Wednesday, state troopers in riot gear and police on horseback broke up a protest at the school hosted by the student group Palestine Solidarity Committee. Nearly 60 people were booked into the Travis County Jail in connection to the protest, Travis County sheriff's office spokesperson Kristen Dark said.

In a statement, the group Concerned UT Austin Faculty decried what it called a decision by administrative leaders to invite city and state police "on horses, motorcycles and bicycles, in riot gear and armed with batons, pepper spray, tear gas and guns to our campus today" to interrupt a peaceful student event.

"The event was to have included teach-ins, study sessions, pizza and an art workshop," the statement said. "There was no threat of violence, no plan to disrupt classes, no intimidation of the campus community. Instead of allowing our students to go ahead with their peaceful planned action, our leaders turned our campus into a militarized zone."

Campus 'no longer a safe and welcoming place'

Some faculty members and students are calling for the removal of University of Texas President Jay Hartzell, saying the police response - and invitation to bring them to campus - went too far.

Polly Strong, the president of the UT chapter of the American Association of University Professors, called on faculty to sign a petition of no confidence in Hartzell.

"The President has shown himself to be unresponsive to urgent faculty, staff, and student concerns. He has violated our trust," the petition said. "The University is no longer a safe and welcoming place for the diverse community of students and scholars who until now have called this campus home."

Will Creeley, legal director of the Foundation for Individual Rights and Expression, said the nonpartisan civil liberties group has received requests for assistance since UT Austin's response to student demonstrators. Since joining FIRE in 2006, Creeley told USA TODAY he has never seen such a stark law enforcement response to student expression.

“Adding a lot of law enforcement officers to a peaceful protest – it's easy to imagine how that goes south. It's harder to imagine how that goes right," Creeley said.

Some conservative commentators disagreed and applauded the Texas police response.

“The protest Wednesday at the University of Texas-Austin was a prime example illustrating the difference between how red states and blue states handle respect for the rule of law. Red states meet such challenges with strength, as seen in the cases of Texas Governor Greg Abbott and UT-Austin’s President Jay Hartzell,” blogger Laura Wellington wrote in a commentary for the Western Journal, a conservative news site.

“Blue states take quite the opposite approach. They’ve taught young people to disrespect the rule of law by ensuring there are zero consequences, so now the young militants are running roughshod over Columbia University, New York University and Yale University, among many others," Wellington wrote.

First Amendment issues - public vs private

Columbia University's private school status leaves little room for legal recourse from groups that object to the administration’s response, First Amendment experts say. Students and faculty at most private schools don't have the same protections as those at public schools.

"Columbia can restrict First Amendment rights. They can restrict what students say and what they protest," said Kevin Goldberg, an expert in First Amendment rights at the Freedom Forum, a national group that advocates for First Amendment protections.

Still, Columbia’s decision to suspend students, send in state police officers to shutter demonstrations and arrest protesters was “a pretty dramatic escalation” of common practice at campuses across the nation, said Angus Johnston, an adjunct assistant professor at Hostos Community College of the City University of New York and a historian of student activism.

The Columbia Spectator, a student newspaper, reported the response to its encampments last week marked the first time that mass arrests were made on campus since 1968, when NYPD arrested hundreds of students protesting the Vietnam War.

"The shift that’s happened is not a shift in student tactics, but a shift in administration response," he said. “After Kent State and Jackson State in 1970, there was a period of about 30 years or so where it tended to be fairly unlikely that campuses would respond with mass arrests even in the case of admin building occupations."

“College students today, including Jewish students, are not at the level of support for the government of Israel that we see in their parents or grandparents. And a large group of college politicians and administrators and donors are all lined up on the other side."

This is creating a situation in which students feel justified in their protest and administrators feel justified in their response, Johnston said.

There was a wave of mass arrests in response to the Occupy movement in the early 2000s. But when university police pepper-sprayed demonstrators on the University of California, Davis campus and the incident made national headlines, the trend bucked, Johnston noted.

“It caused a lot of colleges to dial back their tactics again,” he said. “In recent years, it’s not unheard of to have arrests, but to do so so quickly with mass suspensions and arrests of so many students at one time felt like very precipitous escalation.”

'I don't think the cops need to be here at all'

At Northwestern University, undergraduate student Mayán Alvarado Goldberg said she was present when cops first came to take encampment tents down Thursday morning.

“To be honest, it was a little scary,” said the 22-year-old, whose sister is planning to camp out at a California student protest.

“I don’t think the cops need to be here at all,” she said, pointing to nearby people eating carryout kebab.

But given the confrontation in the morning, she had one comment if police returned, and arrests were made: “I guess it shows even peaceful protest will be met with violence.”