Military threats from China and Russia and cyber-terrorism are top defense concerns for the United States, former Defense Secretary William Cohen told students Thursday night at the Dorothy Marvin Betts Theatre.

Cohen, who headed the Pentagon for four years under former President Bill Clinton, explained his agenda to promote peace in other countries.

“Peace is costly, but it is much cheaper than any war,” he said.

Cohen said keeping U.S. military presence in other countries, known as forward deployment, is a hotly contested topic between Republicans and Democrats. He said the strategy reduces the prospect of conflict.

Withdrawing troops would create unstable environments, Cohen said, because other countries would move in where the United States abandons its post.

Cohen, who now serves as CEO of the Cohen Group, an international strategic business consulting firm, said the United States should continue expanding its presence abroad to promote peace, stability and democracy throughout the world.

“With capable, patriotic and diplomatic troops deployed, our friends and enemies make judgements about the United States,” Cohen said.

Cohen said the United States faces many challenges in the 21st century.

Ethnic conflicts and rivalries, drug trafficking and biological and chemical warfare continue to threaten the nation, Cohen said, but the major problems confronting the United States include cyber-terrorism, instability in Russia and the growing power of China, he said.

Cohen said computer “hackers” present a threat to U.S. defense systems.

“We need to protect the critical infrastructure of the U.S.,” he said. “(Hackers) can attack vital systems, which have the possibilities of creating chaos and catastrophes.”

Cohen said political leaders in the United States should continue to engage Russia and China in discussions about peace.

He criticized U.S. media for preventing personal engagement with other countries, claiming press criticism of political junkets often keeps politicians from traveling to other countries. Cohen said civil servants need a more global experience to deal with international issues.

“We need to weave these invisible webs of friendships on a personal basis,” he said.

Cohen responded to a question from a student concerning the controversial School of the Americas, saying the United States is not interested in promoting atrocities. Opponents of the school say the U.S.-sponsored military school promotes killings and violence abroad.

“We are interested in encouraging skillful, not barbaric military practices,” Cohen said.

Cohen was the inaugural speaker in a lecture series sponsored by GW alumnus Robert J. Pelosky, Jr. The series, created to attract prominent speakers to GW’s Elliott School of International Affairs, will serve as a venue to raise debate on current issues around the world, said Harry Harding, dean of the Elliott School.

“This is to be a forum for us to learn together, interact together and leave inspired,” Harding said. “It will include some of the finest practitioners of international affairs.”