Undoubtedly far too many big money congressional contributors involved in the manufacture/procurement of these undependable weapons to permit a change OR investigation. Better several dead marines than Jack Murtha losing a few bucks.
For forty years our military has been outgunned on the front lines because they are saddled with weapons that were selected for political reasons as much or more than performance in combat.
Reading the well documented history of the Vietnam era change from the M-14 to the M-16 will enrage you and bring tears to your eyes.
Many men died needlessly as politicians and lobbyists manuevered to defend their decision to purchase the M-16 by discrediting men on the front lines.
This is just the latest chapter in that story.