"Finally, the adjective “well-regulated” implies nothing more than the imposition of proper discipline and training. See Johnson 1619 (“Regulate”: “To adjust by rule or method”); Rawle 121–122; cf. Va. Declaration of Rights §13 (1776), in 7 Thorpe 3812, 3814"
https://www.supremecourt.gov/opinions/07pdf/07-290.pdf

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