Plausible deniability has a long history in international relations. States use their intelligence services to do abroad covertly what would be unacceptable for armies or diplomats to do overtly. If they can plausibly deny culpability for even egregious violations of other states' sovereignty or national interests, countries usually get a pass. Victims of covert actions sometimes also appreciate the institution because it enables them to avoid responses-like retaliatory use of force-that are undesirable in other ways.

Plausible deniability became a domestic U.S. political tool at least as long ago as the 1960s, when President Johnson ordered the CIA to investigate leaks about covert actions that appeared in Ramparts magazine, knowing the work was illegal; when scandal erupted, Johnson distanced himself from the agency, trying thereby to absolve himself of the primary responsibility he bore. The CIA, according to Henry Kissinger, accepted orders from President Nixon even when they were not written-purposely to protect the president. President Clinton distanced himself from the CIA after the 1994 Aldrich Ames spy scandal broke-as if the agency did not work for him. President George W. Bush, and his senior aides and political allies, implicitly blamed faulty CIA intelligence on weapons of mass destruction for the policy errors that led to the military quagmire in Iraq. And earlier this year, House Speaker Nancy Pelosi sought to deflect criticism that, while the ranking minority member on the House Intelligence Committee in 2002, she knew about and implicitly condoned waterboarding as an interrogation technique by saying the CIA deceived her. Even now, ascendant congressional liberals continue to bash George W. Bush and U.S. intelligence generally.

In all of these cases, politicians used the CIA to deflect responsibility for real or alleged policy failures. The agency was, and is, easy to use as a whipping boy for several reasons. A clear if diminishing culture of selfless service leads CIA officers to be willing to take falls for presidential policies gone awry. They understand and accept that intelligence failures are often publicized, while successes are not. Further, the agency has no special domestic constituency to support it the way the veterans' groups support the military even when generals make big mistakes.

But however attractive the CIA seems for politicians searching for a scapegoat for policy errors, criticizing the agency carries at least four major disadvantages. It deflects responsibility for failures of governance from policy makers to their agents-a serious flaw in a core function of democratic government. And it damages America's soft power. Foreign nations can use domestic demonizing of the CIA as evidence that the U.S. government, and even the country as a whole, is dysfunctional and evil. This self-inflicted injury to America's global reputation damages the efficacy of our foreign-policy initiatives-and is especially harmful to the Obama administration, which wants to appear kinder and gentler than its predecessor.

Extensive political attacks on the CIA also encourage it to search for its own scapegoats, like Blackwater. Contractors can act as convenient fall guys, as they have their own culture of silence and are willing to take unjustified political heat so long as contracts keep coming their way.

All of this political criticism has created huge incentives for the CIA and other agencies to insulate themselves from bad press in other ways. The best way for intelligence services to do this is to be conservative-intellectually, not politically-by offering waffling analyses and withholding warnings until unfolding events become clear enough to ensure organizational safety from recriminations about another forecasting failure. But this, of course, also damages the usefulness of warning messages, and the intelligence services as a whole. As bureaucrats, intelligence officers know it is better to be accused of mediocrity or ignored than to be pilloried for real or imagined offenses. For a decade, worried CIA officials have bought insurance, at personal expense, to protect themselves from the costs of defending themselves from prosecution by their own government for simply doing their jobs-a prospect that, with the appointment of a new special prosecutor to probe the history of CIA interrogations, may now be imminent. Such incentives hurt the government's ability to function and endanger the country.

Attacks on the CIA drove director Leon Pinetta to make an unusual public appeal in early August for a congressional ceasefire. But the feeding frenzy seems unlikely to go away any time soon. With a new set of reports from CIA's inspector general reportedly due for release, CIA bashing remains good political sport. We can expect more recriminations in the weeks and months to come.

John A. Gentry is a former CIA intelligence analyst. He is author of a book and several articles on intelligence issues.