It is up to interpretations of US history.

Thomas Jefferson said:

"The two enemies of the people are criminals and government, so let us tie the second down with the chains of the Constitution so the second will not become the legalized version of the first."

But he did not write bill of rights. It is a belief that founding fathers influenced the bill of tights (in 1791)

http://en.wikipedia.org/wiki/Second_Amendment_to_the_United_States_Constitution in America prior to the U.S. Constitution

Experience

Ideals that helped to inspire the Second Amendment in part are symbolized by the minutemen.^[25]

In no particular order, early American settlers viewed the right to arms and/or the right to bear arms and/or state militias as important for one or more of these purposes:^{[26][27][28][29][30][31][32][33]}

• deterring undemocratic government;
• repelling invasion;
• suppressing insurrection;
• facilitating a natural right of self-defense;
• participating in law enforcement;
• enabling the people to organize a militia system