It's a big deal. Some people feel threatened by guns. Guns, for some, immediately bring to mind feelings of violence, fear, and danger. To them, guns are things that kill people. Nothing else. Others see guns like others see their old dog. It's been with them for years, right by their side during some of their finest memories. It makes them feel relaxed, safe, and comfortable. With perspectives this different, it's no large wonder that people don't all agree.
The Second Amendment itself reads "A well regulated Militia, being necessary to the security of a free state, the right of the People to keep and bear Arms, may not be infringed." While we argue about whether this applies to the individual person having a right to keep and bear arms (the position of gun-rights advocates) or only to the State Militia aka The National Guard (the position of gun-control advocates), the Supreme Court has just issued a controversial ruling pointing towards the former. I think we should note that there is more here in this Amendment than this, and I think that some time spent remembering the context of this sentence can lend some understanding to us.
You must remember, first, that owning guns was an everyday reality for virtually everyone at the time the amendment was written. The idea that a hunting rifle could be banned would have been as outrageous as banning cars today. It was some people's means of food and money -- and I don't mean shootists, I mean hunting. In fact, the right of an individual to own a firearm existed before this amendment as part of British common law. The individual's right to keep and bear arms was essentially assumed here (and remember, the Constitution was intended to lay out the bounds of government rights, not the people's rights).
Second, you must remember that the idea of a standing federal army was not a reality at the time. Armies held during times of peace was actually one of the complaints in the Declaration of Independence. Standing armies were State militias comprised of state residents, not Federal armies. The Articles of Confederation (the documents that held the 13 original states together as a unit after the Declaration of Independence, but before the Constitution was signed into law) created the Continental Army in order to fight the British for freedom, but this viewed as temporary, and when the Second Amendment was written, whether to maintain this Federal army was the subject of hot debate. The Second Amendment was largely a concession or a compromise toward those who disapproved of a standing Federal army, as a way to guarantee that the Federal army could never take away a state's sovereignty. "The state always had the right to maintain its own standing militia in case it had to hold off the federal government" was the essential message.
As Patrick Henry said, "Guard with jealous attention the public liberty. Suspect every one who approaches that jewel. Unfortunately, nothing will preserve it but downright force. Whenever you give up that force, you are inevitably ruined...." This is the attitude of the Second Amendment. The People have the right to maintain the ability to keep the Federal government in check against tyranny. The right to own weapons privately is assumed in this, as is the right to self-defense (another item already a part of British common law before the Constitution was drafted). Early commentary on the amendment confirms this view. The Boston Journal of the Times printed in 1769, commenting on the British Bill of Rights and the King's attempt to disarm the colonists, that "It is a natural right which the people have reserved to themselves, confirmed by the Bill of Rights, to keep arms for their own defence." The right to own a gun was viewed as a NATURAL RIGHT. One of the self-evident, unalienable rights that the people had, and commissioned government to protect.