US intelligence agencies have not supplied UN arms inspectors with the locations of Iraqi chemical, biological or nuclear weapons. It was long thought that American intelligence had nailed the locations of some of this stuff. But if this is the case, they are not sharing the information.  This may be because the US would rather the Iraqis think their weapons are successfully hidden, thus the weapons could be bombed early in a war. If the information were turned over to arms inspectors, the Iraqis might shuffle all their forbidden weapons, making some no longer in known locations. Then again, American intelligence efforts may have simply failed to find these weapons.