Much, obviously, can be done to improve our intelligence capabilities. But we should also be realistic about how good intelligence can ever be when it is based on human beings wrestling with necessarily imperfect knowledge. This passage from the Robb-Silberman report is a critical, but very reasonable account of how what seemed “common sense” assumptions at the time helped foul up our intelligence about Iraq’s WMD:
Throughout the 1990s, therefore, the Intelligence Community assumed that Saddam’s Iraq was up to no good—that Baghdad had maintained its nuclear, biological, and chemical technical expertise, had kept its biological and chemical weapons production capabilities, and possessed significant stockpiles of chemical agents and weapons precursors. Since Iraq’s leadership had not changed since 1991, the Intelligence Community also believed that these capabilities would be further revved up as soon as inspectors left Iraq. Saddam’s continuing cat-and-mouse parrying with international inspectors only hardened these assumptions.
These experiences contributed decisively to the Intelligence Community’s erroneous National Intelligence Estimate of October 2002. That is not to say that its fears and assumptions were foolish or even unreasonable. At some point, however, these premises stopped being working hypotheses and became more or less unrebuttable conclusions; worse, the intelligence system became too willing to find confirmations of them in evidence that should have been recognized at the time to be of dubious reliability. Collectors and analysts too readily accepted any evidence that supported their theory that Iraq had stockpiles and was developing weapons programs, and they explained away or simply disregarded evidence that pointed in the other direction.
Even in hindsight, those assumptions have a powerful air of common sense. If the Intelligence Community’s estimate and other pre-war intelligence had relied principally and explicitly on inferences the Community drew from Iraq’s past conduct, the estimate would still have been wrong, but it would have been far more defensible. For good reason, it was hard to conclude that Saddam Hussein had indeed abandoned his weapons programs. But a central flaw of the NIE is that it took these defensible assumptions and swathed them in the mystique of intelligence, providing secret information that seemed to support them but was in fact nearly worthless, if not misleading. The NIE simply didn’t communicate how weak the underlying intelligence was.