LOS ANGELES, July 5 (Xinhua) -- Student protests at campuses across the United States have been rare as the four-year-old Iraq war drags on, while some scholars have begun speaking out and conducting studies within their own disciplines to make anti-war voices.

    The lack of protest can be attributed in part to a change in character, as nowadays students are more serious about getting a degree, entering the working world and making money, the Los Angeles Times reported Thursday.

    And unlike the Vietnam War in the 1960s, the conflict in Iraq does not play out against a backdrop of civil rights protests and counterculture rebellion.

    Meanwhile, the government has been skillful in limiting the fallout at home by controlling visual images of the war dead and declining to release information on the number of American or Iraqi casualties, leaving student activists to find other issues easier to embrace.

    But some academics are concluding that they must speak out.

    According to the newspaper, Dan Lowenstein, a note neurological professor at University of California, San Francisco (UCSF), recently helped stage an anti-war teach-in on the campus, where UCSF physicians described the psychological damage to children in war zones and the high percentage of brain injuries suffered by American soldiers in Iraq.

    "We must listen to our conscience and speak out," Lowenstein told hundreds of doctors and medical students at the gathering.

    Calling the conflict in Iraq "the silent war," the professor said the absence of a draft and the lack of televised images of battlefield body bags or coffins coming home have helped keep protests to a minimum.

    Linda Bilmes, a Harvard University public policy professor who was an assistant secretary of commerce in the Clinton administration, also addressed the teach-in and expressed her frustration about the lack of student protests against the war.

    Bilmes has co-written a study that estimates the Iraq war will cost more than 1 trillion dollars, far more than the Bush administration's projections.

    "Why are the campuses not overflowing with students saying, 'What is going on here?' One answer is we are not seeing the true cost of the war," she said.

    Mark Rudd, a leader of Students for a Democratic Society (SDS) and the violent Weather Underground in the 1960s, said many of today's students oppose the war but lack organizing skills and the belief that they can make a difference.

    Rudd, who taught math at a community college in New Mexico for 25 years before retiring in December, said that a lot of students on campus are against the war, but they don't know what to do.

    But Rudd said he is optimistic that students will become more organized as the war continues, noting that students on many campuses have begun forming new chapters of SDS.