Gun registration has been the precursor to genocide according to "Lethal Laws," published by Jews for the Preservation of Firearm Ownership.  Authoritarian governments conducted genocide and mass killings of their own populations, first disarming their citizens.  This was done by first demonizing guns, demanding registration, then banning and confiscating, and finally ending up with total civilian disarmament.  Enslavement of the people then followed with limited resistance, as was the case in Nazi Germany, the Soviet Union, Red China, Cuba and other totalitarian regimes of the 20th century.