One Minute Introduction to the Second Amendment
The Second Amendment, America for that matter, can be summed up just by reviewing the preambles of the three main founding documents: Declaration of Independence, Constitution and Bill of Rights.
The Declaration of Independence attests that God-given rights exist implicitly in humankind and that the purpose of government is to secure these rights.
"...that all men are... endowed by their Creator with certain inalienable Rights, that among these are Life, Liberty, and the pursuit of Happiness. --That to secure these rights, Governments are instituted among Men"
The Constitution was written to provide a framework to secure unalienable rights for all time.
"... in Order to ...secure the Blessings of Liberty to ourselves and our Posterity."
And the Bill of Rights was written to specifically declare a number of those unalienable rights to ensure a good government and prevent abuse of power.
"...in order to prevent misconstruction or abuse of its powers, that further declaratory and restrictive clauses should be added: And as extending the ground of public confidence in the Government, will best ensure the beneficent ends of its institution."
The Second Amendment in the Bill of Rights declares that the Militia comprising the general civilian populace is a key to freedom and restricts government from infringing on the right of the people to keep and carry arms.
"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 American Founders understood that freedom can only be protected when the people are vigilant, prepared and able.