Thomas Jefferson on the right to keep and bear arms

Not just a right, but also responsibility

'We established however some, although not all its [self-government] important principles . The constitutions of most of our States assert, that all power is inherent in the people; that they may exercise it by themselves, in all cases to which they think themselves competent, (as in electing their functionaries executive and legislative, and deciding by a jury of themselves, in all judiciary cases in which any fact is involved,) or they may act by representatives, freely and equally chosen; that it is their right and duty to be at all times armed;' -- Thomas Jefferson to John Cartwright, 1824.