Which part of the 2nd amendment says "gun"?
Which part defines the specific "version" of this "gun"?
In answer to your question of "beginning and ending", In my interpretation, "arms" refers to whatever arms of the day, meaning modern, that may be used in personal defense or in combat to defend the free State.
Perhaps, a problem lies with governmental bodies possessing "dangerous and unusual weapons". I personally believe the use of violence in defense of one's self or State should be restricted to whatever force is necessary to end a threat posed by an assailant. If that defensive force is excessive or indiscriminate to the point that it is inflicted (impinging on the rights of others) upon non-combatants, including natural environmental organisms, who are not directly involved in posing a threat to one's self or State, then use of said force would be immoral. Unfortunately, governments, more frequently than individuals, tend to acquire and utilize such indiscriminately destructive weapons for immoral purposes .
No personal insult intended, I don't see how you are aiding either side of this debate.
Frankly, being that you are posting this on a mostly libertarian oriented site, I'm not quite sure that even you know where you stand on this issue.
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