The Second Amendment provides that “A well-regulated Militia, being 
necessary to the security of a free State, the right of the people to 
keep and bear Arms, shall not be infringed.”  The phrase has a specific 
purpose.  That purpose is not
 to authorize government entities to enact laws or regulations that 
limit who could own arms, what kind of arms they could own, or what they
 lawfully did with those arms.  
Unfortunately, too many people, 
including too many serving in government, operate under the delusion 
that the language of the Second Amendment authorizes government 
“regulation” firearms.  These gun control advocates or “big government” 
advocates urge  Too many operate under the delusion that the Second 
Amendment only protects “sporting arms” or “self-defense firearms”.
The purpose of the phrase “well-regulate” was to underscore that the right protected by the Second Amendment included the political right
 of the citizens to have arms (not just firearms) and accessories 
suitable for the people to rise up and displace any existing or future 
government.  Because the Second Amendment protects a political right, 
its purpose is not limited to self-defense, hunting or recreational 
shooting.    The Second Amendment, stating that a well regulated 
(equipped and trained) militia (the citizenry) is necessary to the 
security of a free state, was specifically understood and intended to 
protect also to civilian ownership military grade firearms. 
In 1840, the Tennessee Supreme Court held in Aymette v. State, 21 Tenn. 154 (1840), tha
 
“the arms the right to keep which is secured are such as are 
usually employed in civilized warfare, and that constitute the ordinary 
military equipment. If the citizens have these arms in their hands, they
 are prepared in the best possible manner to repel any encroachments 
upon their rights by those in authority.”
In 1939, the United States Department of Justice submitted a brief to the United States Supreme Court in the proceedings of United States v. Miller,
 in which the Department of Justice stated the following concerning the 
nature of arms that are protected by the Second Amendment from 
government infringement: 
“While some courts have said that the right to bear arms includes
 the right of the individual to have them for the protection of his 
person and property as well as the right of the people to bear them 
collectively (People v. Brown, 253 Mich. 537; State v. Duke, 42 Tex. 
455), the cases are unanimous in holding that the term “arms” as used in
 constitutional provisions refers only to those weapons which are 
ordinarily used for military or public defense purposes and does not 
relate to those weapons which are commonly used by criminals.”
But the advocates of gun control focus on the phrase “well-regulated”
 and exhibit their civics ignorance by completely misconstruing the 
phrase.
Their assertion that “well-regulated” grants authority to 
government to regulate civilian gun ownership was flatly rejected by the
 United States Supreme Court in 2008 in its Heller decision.  In Heller,
 the Court explained that the phrase “well-regulated” described the 
necessity of a well armed, well prepared and well trained citizenry:
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 (referring to “a well-regulated 
militia, composed of the body of the people, trained to arms”).
Thus,
 in complete contrast to the misconstrued use of the phrase would 
suggest, the actual meaning of the phrase has more to do with promoting 
the purchase, ownership, use and expertise with and of firearms – 
including military suitable firearms – by all civilians.  That 
preparedness and expertise was the basis on which the 13 states were 
able to separate from English rule and establish a new nation and it is 
that necessary threat to government tyranny that assures the “security 
of a free state.”