The theater shooting Friday in Colorado has renewed gun control debate in the United States.
The Colorado shooter was able to arm himself because gun ownership in the United States has been protected by the U.S. Constitution since 1791. At that time, the Bill of Rights, the first 10 amendments to the Constitution, were ratified to protect personal freedoms that had been curtailed by Britain, the recently defeated colonial power.
The Second Amendment says, "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."
But a background check is now required for anyone seeking to buy a gun, to guard against selling to criminals and people who are mentally ill.
Gun control advocates say those limits are not enough and say strengthened controls will cut the 10,000 murders committed by firearms each year in the United States.
Despite the violence, a Gallup poll last year found nearly half of all American adults have a gun on their property and only one-in-four Americans favor banning handguns.
This has not stopped calls in the U.S. Congress for tighter gun regulations. Representative Earl Blumenauer, a Democrat from Oregon, told the House of Representatives Monday, "The 70 killed or wounded [in the Colorado shooting] are the latest in a pattern that happens repeatedly, predictably, with overall loss of life being in the tens of thousands over the years."
Gun rights are defended by the powerful lobbying group, the National Rifle Association, which argues that the right to bear arms is "the fundamental right that separates us from all other nations on earth. There is no greater freedom than the ability to own a firearm to protect yourself, your family, your community and your country."