In reply to "Why the CDC was prevented from clamping down on this plague is a real wonder":  Indeed.  But that isn't all.  Since 1996 (the Dickey Amendment), Congress has prevented the CDC from studying the effects of firearm violence in the USA.  The NRA specifically lobbied for that law.  They are glad that, for the past 20 years, no official data exist on the impact of that plague in our society.