"...Composition C4: 91% RDX, 9% non-explosive plasticizers. This compound is used in mines and hand grenades..."
The material missing is not esoteric material. These are common military explosives.
Why they did not destroy the bunker in the first place is another question, but not one on a Presidential level.
Latest Zogby Tracking Shows Big Shift for Bush (Monday, 25 October, 2004)