In the spring of 1954, the US Senate convened hearings at the instigation of Senator Joseph McCarthy to press his anticommunist investigations into the Department of the Army. The hearings were broadcast live on television, and the American public was able to witness firsthand the tactics McCarthy used to intimidate his foes. At a critical moment in the hearings, a key governmental witness, Army lawyer Joseph Welch, rose to defend one of the junior Army lawyers whose career, Welch alleged, McCarthy had destroyed. Welch turned to McCarthy and memorably intoned: "Let us not assassinate this lad further, senator. You have done enough. Have you no sense of decency, sir, at long last? Have you left no sense of decency?" It was remarkable political theater and historians credit it with breaking the back of McCarthy's attack on the Army, which in turn broke the back of his anticommunist efforts. In short order, McCarthy's allies abandoned him, he was discredited, and he left the Senate in disgrace.
We may be about to witness a McCarthy-Army-Welch moment in the debate over Iraq. This time, the role of McCarthy is played by MoveOn.org, a liberal political group that launched its own attack on a respected US Army figure.
In today's New York Times, the day that General David Petraeus would give his long-awaited, congressionally mandated report on his military activities in Iraq, MoveOn.org ran a full-page advertisement that accused Petraeus of activities befitting a traitor. The advertisement alleges, without evidence, that Petraeus is not going to give his honest, professional assessment of the situation in Iraq but instead will be ''cooking the books'' to curry favor with the Bush White House. The heart of the advertisement is a juvenile pun on Petraeus's name: General Betray Us?
The MoveOn.org ad is vicious, and would garner comment even if it were merely one more primal scream in the coarse blogosphere debate over Iraq. But it is not an angry e-mail or blog entry. It is a deliberate attack on the senior Army commander, in a major daily newspaper, with the intention of destroying as much of his credibility as possible so that his military advice could be more easily rejected by antiwar members of Congress.
The attack was part of an elaborate effort to undermine public support for the Iraq war, and was foreshadowed by an unnamed Democratic senator who told a reporter, "No one wants to call [Petraeus] a liar on national TV ..... The expectation is that the outside groups will do this for us." The effort is funded by powerful special interests, and has all the trappings of a major political campaign.
Precisely because it is so vicious, so public, and so deliberate, the attack on Petraeus cannot be ignored by either side in the Iraq debate.
Supporters of the war are duty-bound, like Joseph Welch, to rise and ask of war opponents, ''Have you left no sense of decency?'' Antiwar members of Congress, like Senator McCarthy's allies, are obliged to answer.
Let us be clear. It is legitimate to grill Petraeus on his testimony and to ask him tough questions about the strategy he has been pursuing. It is legitimate to disagree with him, or to conclude that an alternative course of action has a better chance of advancing US interests in the region. Healthy civil-military relations do not depend on accepting uncritically anything a senior military officer says. Quite the opposite, they depend on a full and frank exchange of views.
It is not legitimate, however, and it is exceedingly corrosive of healthy civil-military relations to question the general's patriotism when his views differ from yours and are inconvenient for one's political agenda.
This is a defining moment for the antiwar faction. They can continue on the path on to which they have veered, repeating some of the worst mistakes in American history. Or they can make a clean break with the past, police their own ranks, and promote a healthy, critical, public debate about the best way forward in Iraq.
Peter D. Feaver is a political science professor at Duke University and author of ''Armed Servants: Agency, Oversight, and Civil-Military Relations.'' He served on the National Security Council staff under Presidents Clinton and George W. Bush.