Second Amendment

Amendment II
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.

While the Supreme Court is considering the Washington DC gun ban, I'd like to give my interpretation of the Second Amendment.
The U.S. Constitution Section 8, Clause 14 makes it the responsibility of Congress to arm a militia. The Founding Fathers were aware of the cost of outfitting them and, most importantly, were aware that the struggle they had just been through could be repeated sometime in the future. This could have been a money saving idea but certainly it was their way of insuring that the populace would not be unarmed and helpless in the face of any future crisis. Including the crisis of their own newly formed government becoming oppressive and tyrannical. The founding fathers were aware of the need to be prepared to fight tyrants.
Remember how the Declaration of Independence starts out?

When in the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth, the separate and equal station to which the Laws of Nature and of Nature's God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation.

I also think it's clear, as it is in the First Amendment, that "the people" is a reference to individual citizens, not groups.