For three decades, the story of gun control was one of notorious crimes and laws passed in response, beginning with the federal law that followed the assassinations of Robert F. Kennedy and Dr. Martin Luther King Jr. in 1968. But after a Democratic-controlled Congress in 1994 passed bills proposed by President Clinton to restrict certain kinds of assault weapons and to create a national system of background checks for gun purchases, the political pendulum began to swing the other way. President Bush's defeat of Al Gore in the 2000 presidential election was attributed in part to the perception among gun owners that Mr. Gore was "anti-gun."
In the wake of the shootings in Arizona in January 2011, in which a gunman with a Glock semiautomatic killed six people and wounded 14 wounded, including a congresswoman, polls will likely gauge the public’s support for stricter gun control laws.
In Washington, bills were being drafted to step up background checks, create no-gun zones around members of Congress and ban the big-volume magazines that allowed the Tucson gunman to shoot so many bullets so fast. Gun control advocates say they believe the shock of the attack has altered the political atmosphere, in no small part because one of the victims is a member of Congress.
Yet gun rights advocates and lawmakers on both sides of the aisle said that there was little chance the attack would produce significant new legislation or a change in a national culture that has long been accepting of guns. If anything, they said, lawmakers are less receptive than ever to new gun restrictions.
Recent battles have taken place in the courts, revolving around fundamentally differing interpretations of the oddly punctuated, often-debated Second Amendment, which reads: "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 Supreme Court in 2008 embraced the view that the Second Amendment protects an individual right to own a gun for personal use, ruling 5 to 4 that there is a constitutional right to keep a loaded handgun at home for self-defense.
But the landmark ruling in District of Columbia v. Heller addressed only federal laws; it left open the question of whether Second Amendment rights protect gun owners from overreaching by state and local governments.
On June 28, 2010, the court ruled in another 5-4 decision that the Second Amendment restrains government's ability to significantly limit "the right to keep and bear arms." The case involved a challenge to Chicago's gun control law, regarded as among the strictest in the nation.
Writing for the court, Justice Samuel Alito said that the Second Amendment right "applies equally to the federal government and the states."
The McDonald v. Chicago ruling is an enormous symbolic victory for supporters of gun rights, but its short-term practical impact is unclear. As in the Heller decision, the justices left for another day the question of just what kinds of gun control laws can be reconciled with Second Amendment protection.
A 1939 decision by the Supreme Court suggested, without explicitly deciding, that the Second Amendment right should be understood in connection with service in a militia. The "collective rights'' interpretation of the amendment became the dominant one, and formed the basis for the many laws restricting firearm ownership passed in the decades since. But many conservatives, and in recent years even some liberal legal scholars, have argued in favor of an "individual rights'' interpretation that would severely limit government's ability to regulate gun ownership.
In May 2009, President Obama signed into law a provision allowing visitors to national parks and refuges to carry loaded and concealed weapons. The amendment was added to a consumer-friendly credit card measure that the president has said is important.
The provision represents a Congressional victory that eluded gun rights advocates under a Republican president.
But in July 2009, the Senate turned aside the latest attempt by gun advocates to expand the rights of gun owners, narrowly voting down a provision that would have allowed gun owners with valid permits from one state to carry concealed weapons in other states.
When President Obama took office, gun rights advocates sounded the alarm, warning that he intended to strip them of their arms and ammunition.
But Mr. Obama has been largely silent on the issue while states are engaged in a new and largely successful push for expanded gun rights, even passing measures that have been rejected in the past.
And, gun control advocates say, Mr. Obama has failed to deliver on campaign promises to close a loophole that allows unlicensed dealers at gun shows to sell firearms without background checks; to revive the assault weapons ban; and to push states to release data about guns used in crimes.