And not "not conceal". I suppose all those people carrying derringers, back in the day, were violating the Constitution.
According to historian Saul Cornell, states passed some of the first gun control laws, beginning with Kentucky's law to "curb the practice of carrying concealed weapons in 1813." There was opposition and, as a result, the individual right interpretation of the Second Amendment began and grew in direct response to these early gun control laws, in keeping with this new "pervasive spirit of individualism." As noted by Cornell, "Ironically, the first gun control movement helped give birth to the first self-conscious gun rights ideology built around a constitutional right of individual self-defense.