In March, for the first time in the nation’s history, a federal appeals court struck down a gun control law on Second Amendment grounds. Only a few decades ago, the decision would have been unimaginable.

There used to be an almost complete scholarly and judicial consensus that the Second Amendment protects only a collective right of the states to maintain militias. That consensus no longer exists — thanks largely to the work over the last 20 years of several leading liberal law professors, who have come to embrace the view that the Second Amendment protects an individual right to own guns.
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