Two American professors on their first visit to Israel since the publication of their book critical of the powerful pro-Israel lobby in Washington faced a sometimes-testy reception at one of the nation’s most prestigious universities.

About 200 students and faculty members crammed into a stuffy lecture hall at the Hebrew University on Thursday and grilled John Mearsheimer and Stephen Walt for more than two hours about their best-selling book.

The pair argue that pro-Israel special interest groups have manipulated the U.S. political system to promote policies that favor Israel and run counter to American interests. Jewish American groups and U.S. administration officials have criticized them.

The authors said Thursday their goal was to draw a lively academic debate over a topic that was perceived as taboo.

“If you bring up the Israel lobby, you are asking for trouble,” Walt said as he opened his lecture. He said he knew he was “playing with fire” when he wrote the book, but said he would not be deterred by personal attacks.

Critics have charged Mearsheimer, a University of Chicago professor, and Walt, of Harvard University, with shoddy scholarship, faulty logic and even anti-Semitism.

The attacks have been compounded because Islamic militants, Holocaust deniers and even former Ku Klux Klan leader David Duke are among those who have praised the book, although some mainstream analysts have said their work raised legitimate points.

The classroom erupted in excited conversation as the authors took questions. The exchange was mostly cordial, with the professors eliciting some laughs. But it got testy at times.

International relations student Liad Gilhar, 25, accused the professors of distorting facts and providing fodder for anti-Semites.

“You need to choose your words carefully,” Gilhar said.

Walt shot back: “With all due respect, I don’t think it is my words that harm Israel, but rather Israel’s actions.”

A professor criticized the authors for failing to condemn Iranian President Mahmoud Ahmadinejad, who has called for Israel to be wiped off the map. “I don’t think he is inciting to genocide,” Walt responded.

Mearsheimer said Israel’s “brutal” treatment of Palestinians helped fuel terrorism against the United States and that, unlike in Israel, there was no healthy debate on the matter in America.

“The U.S. media coverage is heavily slanted in Israel’s direction,” he said.

Korina Kagan, a political science lecturer, said she essentially agreed with their thesis and was appalled by the attacks against them, especially from academic circles.

“The smear campaign against them is worse than anything they have ever written,” she said, adding that many of their positions are shared by commentators in the Israeli media. “We need to have a free academic exchange.”

Mearsheimer and Walt were invited to Israel by Gush Shalom, a small, ultra-dovish political group, to speak about their book, “The Israel Lobby and U.S. Foreign Policy,” published last year.

The two said they decided to speak at Hebrew University in order to address a more diverse audience.

“It is telling that the guests came to Israel and were hosted by a fringe group and had to solicit themselves to appear here,” said Arieh O’Sullivan, a spokesman for the Anti-Defamation League in Israel. “It’s not academia, it’s like a traveling carnival show.”