WASHINGTON — The Supreme Court's landmark gun rights ruling yesterday settled an old debate over the Second Amendment. It's not all about muskets and militia service. Americans do, in fact, have an individual right to bear arms for self-protection.

But in striking down a handgun ban in Washington, D.C., a crime-plagued city with the nation's toughest gun control laws, the court touched off a fresh debate over how far government can go to protect the public. Some regulations on possession and transfer of guns are "reasonable," the court said in a 5-4 decision.

The decision came on the last day of the 2007-08 term. Justice Antonin Scalia declared for the majority that the Second Amendment provides an "individual right to have and use arms in the home."

He rejected the notion that the gun right must be connected to service in the militia, as many judges had ruled and Washington officials had argued. Scalia added, however, that the gun right is not absolute. He said prohibitions on the possession of firearms by felons and the mentally ill, and laws forbidding the carrying of arms in government buildings would stand.

The Washington case "is merely the opening salvo in a series of litigations that will ultimately resolve what weapons and persons can be regulated and what restrictions are permissible," said Robert Levy, the lawyer who helped craft the case against the capital's gun ban and paid for the suit and appeals.

"Because of Thursday's decision, the prospects for reviving the original meaning of the Second Amendment are now substantially brighter," Levy said.

"Hallelujah. Praise the Lord and pass the ammunition," said David Schenck, a Dallas lawyer who filed a brief on behalf of the Texas State Rifle Association and sister groups in 42 other states.

The question for courts, city councils and legislatures — including Hawai'i's — to sort out in coming years will be: Which restrictions pass muster?

This is the first time the court explicitly said the Second Amendment protects an individual right to gun ownership, and was its first hard look at gun rights since 1939.

Dissenting Justice John Paul Stevens, speaking in open court, blasted the majority for establishing what he called a "newly discovered" right and accused the conservative justices of violating the principles of judicial restraint they frequently espouse. The court, Stevens said, "is making new law today."

The court had not conclusively interpreted the Second Amendment since its ratification in 1791. The issue was whether the amendment protects an individual's right to own guns no matter what, or whether that right is tied to service in a state militia — a now-archaic grouping of citizens.

Joining Scalia were Chief Justice John Roberts and Justices Samuel Alito, Anthony Kennedy and Clarence Thomas. The other dissenters were Justices Ruth Bader Ginsburg, Stephen Breyer and David Souter.

PLAINTIFF HAILS VERDICT

The case was filed by Dick Heller, a security guard who was refused permission to keep his handgun at his home in the nation's capital.

"I'm thrilled I am now able to defend myself and my household in my home," Heller said after the opinion was announced.

His attorney, Alan Gura, called the ruling a blockbuster.

"There are thousands of gun laws in the United States. Some of them are going to survive, and some of them might not," he said.

The last Supreme Court ruling on the matter came in 1939 in U.S. v. Miller, which involved a sawed-off shotgun. Constitutional scholars agree it did not answer the question of individual versus collective rights.

At the National Rifle Association, which is preparing lawsuits in Chicago and San Francisco, chief lobbyist Chris Cox called it a "historic day."

"This is an individual right that applies to all Americans, not just rich people, not just the elites," he said, adding, "It's not as if every gun law in the country is going to be struck down."

In Washington, Mayor Adrian Fenty warned that "more handguns in the District of Columbia will only lead to more handgun violence." The mayor emphasized that the ban on carrying guns outside the home stands.

Until now, Washington let only retired police register weapons, banned carrying unlicensed handguns and required any firearm at home to be unloaded and disassembled or kept with a trigger lock. Scalia wrote that made it impossible for citizens to keep a gun at home "for the purpose of immediate self-defense" — a violation of individual rights, he said.

CANDIDATES' REACTIONS

Presumptive GOP presidential nominee John McCain said: "Today's decision is a landmark victory for Second Amendment freedom in the United States. For this first time in the history of our Republic, the U.S. Supreme Court affirmed that the Second Amendment right to keep and bear arms was and is an individual right as intended by our Founding Fathers. I applaud this decision as well as the overturning of the District of Columbia's ban on handguns and limitations on the ability to use firearms for self-defense."

Barack Obama, the presumptive Democratic nominee, said "today's ruling, the first clear statement on this issue in 127 years, will provide much-needed guidance to local jurisdictions across the country."

McClatchy-Tribune News Service, USA Today, Associated Press and the Washington Post contributed to this report.