An incensed Rachel Maddow reacts to horrific new details on the Sandy Hook shootings, and the idiotic audacity of GOP Sen. Ted Cruz lecturing longtime Senator - and witness to gun violence - Dianne Feinstein on the Constitution. Infuriating, stomach-churning, here's why.

Update: In a particularly insane speech at CPAC - in which, interestingly, he repeatedly used the word "insane" - the NRA's Wayne LaPierre argued that background checks would just leave gun-owners' information susceptible to Chinese and Mexican hackers, and that rapists can best be stopped by "a good woman with a gun." Just wow.

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