CNN Moderator: Tonight's guest is Harvey Klehr, Ph.D., a professor of political science at Emory University. He was one of the first Western researchers allowed access to the archives of the Comintern, and is a co-author of "The Secret World of American Communism," "The Amerasia Spy Case: Prelude to McCarthyism" and "The Soviet World of American Communism."

Chat Participant: Mr. Klehr... what proportion of the American population regularly monitored the McCarthy "Red" hunt, and is there any estimate to their opinion to it?

Dr. Harvey Klehr: The McCarthy hearings were the first televised congressional hearings. They had a huge television audience. He had the support of a substantial proportion of the population, probably a majority until he attacked the military.

Chat Participant: Prof. Klehr, in "Storming Heaven," you went to some lengths to insist that the CPUSA was NOT an agent of Soviet policy, however duped ideologically they may have been. Do you now reverse that position?

Dr. Harvey Klehr: Yes, I have revised my opinion based on what I discovered in Russian archives. Neither I, nor any other American academic, expected to find so much evidence of monetary support and use of the CPUSA for espionage.

Chat Participant: How was the McCarthy era different than the "red scares" of the 1920's? Why is it considered more important?

Dr. Harvey Klehr: It was much more intense. It involved several prosecutions for espionage. And the CPUSA was a much more powerful organization in American society.

CNN Moderator: What shocked or surprised you most in the Soviet archives?

Dr. Harvey Klehr: The revelations that that the CPUSA had been intimately involved in Soviet espionage and that the leadership of the CPUSA not only knew about the espionage, but actively participated in it. This included Earl Browder, head of the party.

Chat Participant: Sir now that we know for sure that the Rosenbergs were guilty (at least one of them) do you think we will see less left wing handwringing and more right wing sympathy for McCarthyism excesses?

Dr. Harvey Klehr: I think both were guilty, although Ethel was only a minor participant in the espionage. I doubt that American radicals or the left are going to stop the "handwringing", in part because many of them insist that the new evidence is unreliable or forged. It has generated right-wing triumphalism, some of it justified.

Chat Participant: Dr. Klehr, is it your thesis that the American Communist Party was a vehicle for espionage primarily, or would you agree that most rank and file Party members were social idealists who sincerely if mistakenly believed in the goodness of the Soviet leadership and developed a narrow-minded inability to view their "utopia" critically? The latter thesis would make them naive, but not traitors.

Dr. Harvey Klehr: Most of the rank and file were idealists of various sorts, but the Party leadership was well aware of what was going on. And those idealists were used by the leadership. Several hundred American communists were mixed up in the espionage.

Dr. Harvey Klehr: I believe that Aileen Kraditor was right. Many American Communists may not have known about the espionage but lots of them would not have objected to it if they knew.

Chat Participant: You would then reject, I presume, Professor Kraditor's contention that Party members were not so much perfidious as lost in a "special universe" of psychological unreality.

Chat Participant: Did espionage have a significant impact on one side more than the other (KGB/CIA)?

Dr. Harvey Klehr: The KGB had several hundred sources in the U.S. during the 1940s; the CIA never had more than a handful in the Soviet Union. The Soviet sources included several high-ranking government officials. Clearly, they did much better. There was a CPUSA to recruit from; there was no Democratic or Republican party in Moscow.

Chat Participant: Ohh, left wingers, myself included, are not "handwringing" over the Rosenberg's being guilty or not. Our anger of that period stems from the suspension of normal civil rights in order to publicly try and convict people without due process. What is your feeling on that issue?

Dr. Harvey Klehr: The Rosenbergs' civil rights were not violated. You can believe that they should not have been executed, but still recognize that they were found guilty in a trial during which they had all the legal rights of any accused. Their case was reviewed by various courts and the sentence carried out. Again, the execution may have been an overreaction, but it hardly involved the suspension of civil rights.

Chat Participant: The CPUSA was funded and controlled from Moscow. Were there any other left wing organizations in the West that received Soviet support?

Dr. Harvey Klehr: Every communist party in the world received Soviet money. Also, a number of left wing organizations, ranging from the World Peace Council to the U.S. Peace Council got Soviet money. Much of the documentation has been published in the Russian press.

Chat Participant: Dr. Klehr -- Emory grad here! Was anyone able to successfully deflect the charges made against them by McCarthy & Co.?

Dr. Harvey Klehr: A number of people did so, ranging from General Marshall to Dean Acheson. Even some relatively obscure people stood up to McCarthy, with the help of journalists like Edward Murrow. But, he also ruined a number of innocent people.

Chat Participant: To what extent was CPUSA information critical in the making of the soviet A-bomb?

Dr. Harvey Klehr: Extremely critical. In addition to Klaus Fuchs, a British spy at Los Alamos, there was Ted Hall. Those two gave the USSR virtually every secret of the atomic bomb. Soviet intelligence estimated that they saved the Russians two years of work.

Chat Participant: Dr. Klehr - can you explain why Joseph McCarthy is universally pilloried and his motive to root communism from American government universally ridiculed?

Dr. Harvey Klehr: Because McCarthy was a demagogue. He accused innocent people, misused evidence and couldn't tell a communist spy from a fellow traveler. He gave anti-communism a bad name.

Chat Participant: Mr. Klehr. How do you know that these American Communists would not have objected. I do not believe in communism, but you seem to be proposing that these people would agree with an act of treason. Let's not be too generalistic, please.

Dr. Harvey Klehr: I shouldn't generalize and say all or most. Let's leave it at the fact that a number of rank and filers knew about the Party's connections with Soviet intelligence - they themselves were not participants - and never came forward.

Chat Participant: Dr. Klehr, your scholarship is considered extremely right wing; what resources do you use to do your work?

Dr. Harvey Klehr: I use Russian archives, American government archives and digging in whatever material I can unearth. If telling the truth about Soviet espionage qualifies someone as right wing, that's a pretty scary commentary on America. The position I hold on this issue is no different that the one held by Arthur Schlesinger or Sidney Hook in the 1940s. They were considered leftists.

Chat Participant: I couldn't help but notice the answer about the bomb centered on Fuchs and Hall and not the Rosenbergs. Did they give any critical information?

Dr. Harvey Klehr: The Rosenbergs provided some useful information via David Greenglass. They were far more valuable to the Soviets for Julius's industrial espionage, although the atomic information was helpful.

Chat Participant: Dr. Klehr -- Was the plot involving the Soviet doctors simply a case of Stalin's paranoia or was there some more complicated scheme involved on his part?

Dr. Harvey Klehr: His anti-Semitism. He hated Jews and was planning a massive pogrom to send millions of them to Siberia.

Chat Participant: Mr. Klehr, what is your opinion on Alger Hiss?

Dr. Harvey Klehr: The Venona decryptions indicated that he was a Soviet spy. Allan Weinstein has a new book coming out next year, which contains irrefutable proof from Russian archives that Hiss was a Soviet agent of long-standing.

Chat Participant: Where there any major differences of opinion between American 'Communists' and 'Marxists'? Given the differences between strict 'Marxism' and the Communism-Leninism that developed in the Soviet Union, I would expect there probably were philosophical differences as to how American communists should accomplish their goals. Where there?

Dr. Harvey Klehr: There were plenty of American Marxists who were not Communists. They included people in the Socialist Party and other left wing organizations. Within the CPUSA there were no differences because dissenters were expelled.

Chat Participant: Harvey, have you ever joined the communists to gain insight into their thinking?

Dr. Harvey Klehr: No, can't say that I have. I don't think they would have me.

Chat Participant: Dr. Klehr, isn't it true that Stalin lay dying for several hours and the people around him were unwilling to help him because he was planning another purge?

Dr. Harvey Klehr: Yes. There's some evidence that Beria told one of his men not to get a doctor.

Chat Participant: I'm always skeptical of the words "irrefutable proof", as any historian should be. What kind of checks do you apply to your sources to determine their accuracy, or lack thereof?

Dr. Harvey Klehr: Documents from Russian archives that name Hiss as an agent. Why would the Russians have forged documents? I think that's irrefutable proof.

Chat Participant: Are there still a significant number of Communist believers in the USA?

Dr. Harvey Klehr: There are still about two or three thousand members of the CPUSA, which is still led by Gus Hall, the longest-serving head of a Communist Party in the world.

Chat Participant: Would you characterize all members of the CPUSA as traitors? If not, how would you make the distinction?

Dr. Harvey Klehr: No, I would not. Traitor has a very specific meaning. Even Communist spies were not traitors because we were never at war with the USSR.

Chat Participant: Do you think Stalin would've become another Hitler, but with Communism, had he lived longer?

Dr. Harvey Klehr: He was another Hitler. In fact, Stalin killed more people than Hitler. Hitler killed more Jews, but Stalin ranks second as a murderer of Jews. And no one killed more communists than Joseph Stalin.

Chat Participant: Dr. Klehr, do you think that the U.S. government may have evolved a more Socialist "slant" if it had not been for the Cold War?

Dr. Harvey Klehr: It's possible that the American left would have done better. Certainly, the American labor movement would have been more left. On the other hand, the left has never done particularly well in America.

Chat Participant: How does the CPUSA justify their support of a socio-political system that has proven a failure (ala USSR)?

Dr. Harvey Klehr: The CPUSA insisted that whatever problems there were in the USSR were temporary and caused by the depredations of international capitalism.

Chat Participant: Mr. Klehr, What was the extent of the role Alger Hiss played in the State Department, specifically regarding the Yalta Conference? Did he have any significant impact on post-war planning?

Dr. Harvey Klehr: Hiss was a mid-level bureaucrat. He did not make policy. I don't think he had a major impact at Yalta.

Chat Participant: Mr. Klehr do you think the CPUSA was in any moment a real danger for the American political system?

Dr. Harvey Klehr: Not as a political movement. The danger came mostly from espionage and the fact that most of the spies were Party members. Once they had been rooted out of the bureaucracy, there was very little danger.

Chat Participant: Dr. Klehr; Who led the charge to bring down McCarthy?

Dr. Harvey Klehr: It was a coalition. But a combination of journalists, the Democratic party and the leadership of the Republican party, which had concluded that McCarthy was a liability.

Chat Participant: Andy, how about asking Mr. Klehr to restate the premise of his book, or, at least, explain what he meant by the title. (for those of us who tuned in late).

Dr. Harvey Klehr: The premise of the book is that there was a secret world of American communism. In Moscow archives, I found voluminous details about something called the secret apparatus, which was a Party unit that cooperated with Soviet espionage.

Chat Participant: In practical terms, to the average American, was the espionage issue important?

Dr. Harvey Klehr: Yes, it was. Remember that McCarthy burst into prominence after Americans learned the USSR had exploded an atomic bomb, after China had gone communist and after the Korean war started. People were frightened and convinced that spies had helped undermine America after the success of World War II.

CNN Moderator: What information, now available, would have had the most impact on the course of the Cold War had it been known decades ago?

Dr. Harvey Klehr: The extent of Soviet espionage. The Rosenbergs and Hiss were the tip of a very large iceberg. There might well have been even more anti-Communist sentiment if the secrets revealed in Venona decryptions had been known at the time.

Chat Participant: Did you findings lead you to believe that McCarthy was responsible for actually getting rid of all spies from the bureaucracy, or was it just easy marks that were purged? Did he miss any real threats?

Dr. Harvey Klehr: McCarthy, as far as I know, was not responsible for finding any Soviet spies. In fact, he probably discredited efforts to finds them, because guilty people claimed McCarthyism when they were accused by others.

Chat Participant: Dr. Klehr, what was the climate at Emory University in terms of espionage during the Cold War?

Dr. Harvey Klehr: We haven't found any. Do you know of anyone?

Chat Participant: How much of the declassified documents you used were full of black marker ink?

Dr. Harvey Klehr: The Russian documents are not censored. The Venona material has a few blackouts of names. FBI files released under the FOIA are often heavily censored.

Chat Participant: Since we already had a number of laws against espionage -- if that indeed is the main beef against the Communist Party -- then wasn't all the hundreds of local, state, and federal laws against Reds for more purpose than to stop espionage? Was there not more to this than just fear of spying?

Dr. Harvey Klehr: A lot of it was superfluous or stupid.

Chat Participant: Do you think your research has influenced any of the current espionage business?

Dr. Harvey Klehr: My co-author and I testified before Senator Moynihan's committee on secrecy in 1995 after our book was published and it apparently played a small role in helping get the Venona material released.

Chat Participant: How much did the U.S. pressure allied foreign governments to root out Communists or expose party members in their countries?

Dr. Harvey Klehr: A good bit. For example, we threatened to withhold scientific and atomic cooperation from Australia until they set up a counter-espionage unit to root out spies.

Chat Participant: Did McCarthy believe in his own cause? or was he using the paranoia to further his own political agenda?

Dr. Harvey Klehr: I think he was a charlatan. He was about to be defeated for reelection in 1950, needed an issue and hit upon communism. He knew nothing about it and I don't think he cared much either.

Chat Participant: Do you believe any of the Red Scare was to stifle dissent at home and to control the labor union, which, after all, had led 6-9 million workers on strike in '45 and 46?

Dr. Harvey Klehr: I'm sure that some people had that as a motive, but among the strongest anti-Communists were American labor leaders who had their own reasons for hating communism. The CIO expelled communist-dominated unions in 1948-49.

Chat Participant: What type of sacrifice did it take for Americans and Soviets to become spies? Was there a profile of a typical spy?

CNN Moderator: Someone is thinking of a new career?

Dr. Harvey Klehr: Most Americans who spied for the USSR were Communists. They did not take money - like (Aldrich) Ames. They were idealists convinced that they were serving the cause of humanity. Many had either been born in Russia or had parents born there.

Chat Participant: Have you read Senator Moynihan's book on secrecy and if so, do you like it?

Dr. Harvey Klehr: Yes, I think it's a very good book, both insightful and revealing.

Chat Participant: Did Communism and Socialism really represent such a threat to U.S. interests? Or was it the loss of 'technological edge' in the hands of a political adversary which drove the 'spy-hunts'?

Dr. Harvey Klehr: It was concern that American citizens were aiding a foreign government and giving American military secrets to a foreign power. We prosecute people for that - even when the power is a friendly one. Witness Jonathan Pollard.

Chat Participant: What about the issue of "moral equivalence?" Is it really fair to compare the U.S. "red scare" to the atrocities under Stalin?

CNN Moderator: That issue was raised in a Washington Post editorial.

Dr. Harvey Klehr: I don't think it is a fair comparison. The gulag began in the 1920s. Stalin murdered millions of people. Even if you believe the Rosenbergs were unjustly executed, that's two people compared to the tens of millions Stalin killed. No comparison.

Chat Participant: Do you think the outlawing of the Communist Party was justified?

Dr. Harvey Klehr: No and the CPUSA was never outlawed.

Chat Participant: How did the Soviets go about recruiting Aldrich Ames or the typical spy?

Dr. Harvey Klehr: During the 1940s they targeted particular people and sounded them out. But many people were walk-ins - they volunteered to spy.

Chat Participant: Mr. Klehr, have you extrapolated any historical lessons from that era that you feel could/should be applied today?

Dr. Harvey Klehr: There was a legitimate security issue and the country needed a loyalty program. Such programs, however, are very difficult to run fairly and they run to excess. During periods of national tension, rationality is in short supply.

Chat Participant: Since there is no law against being a Communist or a member of any other party in the United States, why did the "Red Scare" seem to be so destructive?

Dr. Harvey Klehr: Because the CPUSA was supporting the foreign policy of America's major foe at a time when the enemy had nuclear weapons.

Chat Participant: Dr. Klehr, tell us about the contributions of spies such as Philip Jaffe during the Cold War?

Dr. Harvey Klehr: Jaffe was a spy wannabe during WWII. He never actually transmitted info - he wanted to and tried to, but got arrested before he was successful.

Chat Participant: "Needed a loyalty program" precisely where? In the government? In the public schools and colleges (so as not to "infect" impressionable minds)? Where would you have drawn the line?

Dr. Harvey Klehr: Government, military plants, atomic research. Universities - no. Hollywood - no.

Chat Participant: Isn't that a bit glib on Jaffe? He was arrested and never convicted?

Dr. Harvey Klehr: He pleaded guilty to a lesser charge. Take a look at my book on The Amerasia Spy Case.

Chat Participant: Professor Klehr, I don't understand the answer about supporting a foe of America with nuclear weapons. What do the kinds of weapons have to do with threat? Or, is it they supported an enemy?

Dr. Harvey Klehr: Nuclear weapons made the Cold War so frightening because for the first time we faced a foe that had the ability to annihilate us.

Chat Participant: I've read that HUAC's probe of Hollywood after the war was really anti-Semitic in nature, directed toward the Jewish element in Hollywood. How do you feel about this?

Dr. Harvey Klehr: There was an element of that, but it was directed at communists who happened to be Jewish, not Jews in general.

CNN Moderator: Mr. Klehr, do you have any closing comments?

Dr. Harvey Klehr: People interested in this topic can find more information in my books, "The Secret World of American Communism" and "The Soviet World of American Communism", both available from Yale University Press.

CNN Moderator: Thank you for joining us. CNN Interactive hosts Cold War chats every Sunday night from 9:30 to 10:30 p.m., after each episode of CNN's COLD WAR and CNN Postscript air.