The Second Amendment was Ratified to Preserve Slavery
The real reason the Second Amendment was ratified, and why it says "State" instead of "Country" (the Framers knew the difference - see the 10th Amendment), was to preserve the slave patrol militias in the southern states, which was necessary to get Virginia's vote. Founders Patrick Henry, George Mason, and James Madison were totally clear on that . . . and we all should be too.
In the beginning, there were the militias. In the South, they were also called the "slave patrols," and they were regulated by the states.
In Georgia, for example, a generation before the American Revolution, laws were passed in 1755 and 1757 that required all plantation owners or their male white employees to be members of the Georgia Militia, and for those armed militia members to make monthly inspections of the quarters of all slaves in the state. The law defined which counties had which armed militias and even required armed militia members to keep a keen eye out for slaves who may be planning uprisings.