History professors Donald Kagan and Paul Kennedy have publicly disagreed about the proper interpretation of the Sept. 11 terrorist attacks.

And when Kennedy asked Kagan a question about military strategy at a lecture Sunday in Battell Chapel, Kagan realized he might be stepping onto controversial ground.

“I might ruin your Sunday night,” Kagan said. “This may be the time to go.”

But the crowd of 150 decided to stay at the latest lecture in the “Democracy, Security and Justice” series. Kagan, who also gave a Master’s Tea in Saybrook College Monday, answered the question as part of his speech on topics including academia and American policy.

Kagan expressed opposition to the stance he believes universities and academics are taking on the terrorist attacks, Osama bin Laden’s agenda, and U.S. foreign policy. He said there is an “intellectual arrogance” that has surfaced on college campuses in the last eight weeks.

Kagan said the words of those in educational institutions have led to dangerous justifications of the Sept. 11 attacks and increasing anti-Americanism.

“No one should be surprised, as such voices have caused destruction throughout the century,” Kagan said. “Our schools have retreated from encouraging of right and wrong — with the exception of an education in moral relativism that borders on nihilism.”

Kagan also encouraged a return to education promoting civic duty and patriotism.

“The system of education we have now is far from what the founding fathers envisioned. Democracy of all political systems — stands in the greatest need of an education in patriotism,” Kagan said. “Neither family or nation can flourish without love, support, and above all defense.”

He called for an expanding awareness of the threat faced by the United States.

“I am not sure if we all yet understand the consequences of what we are beginning to be engaged in, ” Kagan said.

Kagan fielded questions about the war in Afghanistan and said he is concerned about how such a war will be fought. Kagan responded to a question about combat in light of the Vietnam War.

“Strange you should say that — for the last week I’ve been worried about [Vietnam-like difficulties],” he said in reference to possible complications with ground troops. “[But] there has never been a war won in the air, and I don’t think there will be in my lifetime.”

Kagan said he did not think the United States could withdraw ground troops before winning a decisive victory.

“Unlike Vietnam, this is not a fight we can walk away from,” Kagan said. “If we do not defeat the terrorists, they will destroy us.”

But Kagan said that he sees the possibility of eventual Western peace with the Muslim world if nation-building efforts succeed.

“Who would have believed that Germany and Japan would be what they are now 50 years ago?” Kagan said. “When you take out the bad elements, it’s like a fresh wind blows through.”

Kennedy said he does not have as positive a view of the current conflict.

“I see more difficulties than Don [Kagan] does about defeating the enemies and nation-building,” Kennedy said. “It is important and good to recognize that this is a two-step process, but it can’t be done in six months — perhaps I’m more of a pessimist than he is.”