A militia presumes that those in it possess “military style” arms. There is no such thing as unarmed militias and there is no such thing as militias armed with far inferior weapons like pistols, shot guns, knives and garden tools.
If the individual citizens or people do not have a right to keep and bear arms they may be prevented from forming militias if their own government turns against them. Military style arms in the possession of individual people help guarantee the formation of armed militias if they are necessary to defend the property of the people or any individual.
Frederick Bastiat in 1849 proved that it is not only a right of the individual people to keep and bear arms and to form organized militias but that if they do not have that right there is no foundation for law. Bastiat showed us that all law is nothing but the collective organization of the individual right to lawful defense.
“We hold from God the gift which includes all others. This gift is life—physical, intellectual, and moral life.
But life cannot maintain itself alone. The Creator of life has entrusted us with the responsibility of preserving, developing, and perfecting it. In order that we may accomplish this, He has provided us with a collection of marvelous faculties. And He has put us in the midst of a variety of natural resources. By the application of our faculties to these natural resources we convert them into products, and use them. This process is necessary in order that life may run its appointed course.
Life, faculties, production--in other words, individuality, liberty, property—this is man. And in spite of the cunning of artful political leaders, these three gifts from God precede all human legislation, and are superior to it.
Life, liberty, and property do not exist because men have made laws. On the contrary, it was the fact that life, liberty, and property existed beforehand that caused men to make laws in the first place.
What, then, is law? It is the collective organization of the individual right to lawful defense.
Each of us has a natural right—from God—to defend his person, his liberty, and his property. These are the three basic requirements of life, and the preservation of any one of them is completely dependent upon the preservation of the other two. For what are our faculties but the extension of our individuality? And what is property but an extension of our faculties?
If every person has the right to defend—even by force—his person, his liberty, and his property, then it follows that a group of men have the right to organize and support a common force to protect these rights constantly. Thus the principle of collective right—its reason for existing, its lawfulness—is based on individual right. And the common force that protects this collective right cannot logically have any other purpose or any other mission than that for which it acts as a substitute. Thus, since an individual cannot lawfully use force [except for defense] against the person, liberty, or property of another individual, then the common force—for the same reason—cannot lawfully be used to destroy the person, liberty, or property of individuals or groups.
Such a perversion of force would be, in both cases, contrary to our premise. Force has been given to us to defend our own individual rights. Who will dare to say that force has been given to us to destroy the equal rights of our brothers? Since no individual acting separately can lawfully use force to destroy the rights of others, does it not logically follow that the same principle also applies to the common force that is nothing more than the organized combination of the individual forces?
If this is true, then nothing can be more evident than this: The law is the organization of the natural right of lawful defense. It is the substitution of a common force for individual forces. And this common force is to do only what the individual forces have a natural and lawful right to do: to protect persons, liberties, and properties; to maintain the right of each, and to cause justice to reign over us all.” (Bolding and brackets added)
Those who say that individual citizens and people do not have a right to form a militia or keep and bear arms are denying the foundation of all law. For all law is nothing more than the combined right of individuals to defend their property. No one has a right to harm the life, liberty and possessions of others but all may use force to defend their property from those that do harm without just cause. And all law is that very same thing and cannot be more or less than what an individual has. Therefore, if the individual has no right to a military style weapon neither a right to form a militia, then the United States does not have a right to form an army or military or build or purchase arms and keep and bear them or to hold a court and execute judgments.
 Frederick Bastiat The Law (The foundation For Economic Education) http://www.constitution.org/cmt/bastiat/the_law.html