(printable PDF version) (HTML version) by Carl Conetta. PDA Briefing Memo #27, 25 April 2003. A review of the evidence finds that while UN disarmament missions contributed substantially to disarming Iraq and increasing confidence, they also left substantial residual uncertainties. However, the disarmament missions served to tightly constrain Iraq’s WMD capability and undercut its effectiveness and standard military deterrence would have acted to keep this residual threat in check.