In the first class of the semester, some of Charles Strozier's students cried.
One was a former firefighter with two prosthetic legs. Another was a Marine Corps veteran who had served in Iraq. A third was an FBI agent.
The course on which they are enrolled, held at the John Jay College of Criminal Justice in New York, is simply titled September 11th, 2001.
The college, which lost 67 students and alumni in the attacks 10 years ago, has established a Center on Terrorism staffed by historians, sociologists, anthropologists, psychologists and others.
"Before 9/11, terrorism was almost exclusively studied by political scientists," said Professor Strozier, the programme's director and a historian and psychoanalyst.
"After 9/11, when we became aware of this new form of violence in the world, we realised that you had to come at it from many disciplinary perspectives."
Despite the many routes through which the terrorist attacks of 2001 can be studied, John Jay's programme is surprisingly rare in US higher education.
But elsewhere in the academy, existing areas of scholarship have been affected dramatically by the events of 9/11.
One is the study of Arabic. Enrolment in Arabic-language courses at university level has more than tripled to over 35,000 students, according to the Modern Language Association. It is now one of the top 10 languages taught in the US.
"We all were made aware in a very dramatic way - it couldn't get any more dramatic - that there were groups of people out there about which we knew little or nothing," said Elizabeth Bergman, director of the American Association of Teachers of Arabic.
"Even though the students we are seeing now were very young when those events happened, they come with wonderful youthful idealism that they can help," added Amy Newhall, executive director of the Middle East Studies Association and a lecturer in Near East studies at the University of Arizona.
"There are those who want to make the world a better place. There are those who want to defend their country."
The increase in interest in Arabic has also been fuelled by demand for Arabic speakers.
"It's pragmatism," Dr Newhall said. "Let's be honest: the job market stinks, and there has been an increased focus on the part of funders, including the Department of State, to get students into the field."
Government funding is also paying to send more American students to the Middle East. Last year, 41 per cent of US universities reported increases in study abroad in the Middle East and North Africa, according to the Institute of International Education.
The discipline most propelled by government funding is the new field of homeland security, which a number of universities and colleges have been quick to offer.
But most offerings are "lightweight", Professor Strozier said.
"They're just looking for government money. They're not going to last long, because they don't have any academic substance. If it's going to be in a university, the discussion of terrorism has to be serious."
One course in which 9/11 is discussed with deadly seriousness is Issues in World Politics at Binghamton University in New York state.
It is led by Patrick Regan, a professor of political science who requires students to read a collection of writings by Osama bin Laden alongside those of Nelson Mandela and Martin Luther King Jr.
"Two of those guys we awarded Nobel prizes to," he said. One of them became the president of a country and a revered statesman. I want my students to think about why." Some are offended by the comparison between bin Laden and the other two, he acknowledged.
"I say, 'That's fine. But let's take Nelson Mandela. He admitted to being the head of the armed wing of a terrorist organisation.' It gives them an ethical puzzle. Universities are supposed to do that."
But not many do, Professor Regan conceded. "Academics, like everybody else, can be timid. Academics, like everybody else, can be afraid of consequences. And academics, like everybody else, can be blinded by patriotism."