Jared Lee Loughner is a deeply troubled young man.

No rational person would confront a congresswoman as she talked to constituents, pull a Glock 9 mm semiautomatic with a 30-round magazine, fire until it was empty, and reload with another 30-round clip, as he is accused of doing.

Anyone in his or her right mind would condemn the carnage left outside the Safeway in Tucson: six people dead, and U.S. Rep. Gabrielle Giffords fighting for her life.

"All of Arizona is shocked and deeply saddened by the horrific tragedy that transpired this morning in Tucson," Arizona Gov. Jan Brewer said on the day of the massacre.

But in league with the Arizona Legislature, Brewer made it easy for Loughner and countless other unstable individuals like him to buy, own, conceal and ultimately use firearms.

On April 16 last year, Brewer signed legislation, Senate Bill 1108, making Arizona one of three states where it is legal to carry loaded weapons without a concealed weapons permit.

"I believe this legislation not only protects the Second Amendment rights of Arizona citizens, but restores those rights as well," Brewer declared at the time, cheered by the National Rifle Association.

"SB 1108 will enhance the rights of law-abiding Arizonans," said Chris Cox of the National Rifle Association last April.

At that time, educators at Pima Community College were having difficulties with Loughner. Between February and September, campus cops answered five calls about Loughner causing disruptions.

On Oct. 4, the college delivered a letter to Loughner at his parents' home, informing him that he could not return until mental health professionals attested that "his presence at the College does not present a danger to himself or others." It's not known whether that happened.

But on Nov. 30, Loughner bought a gun at a Sportsman's Warehouse in Tucson. He would have provided basic information: name, date of birth, driver's license.

The clerk would have called a number in Virginia, where operators would have run his name through a database to see whether he had a felony conviction, or been adjudicated as mentally ill. The answer would have come back shortly, negative. Loughner would be loaded, ready to go off.

Arizona, like most states, follows basic federal law, which permits magazines with unlimited numbers of bullets, and requires only the most cursory background check.

"Where Arizona does differ, it is more permissive," said Dr. Garen Wintemute, the UC Davis medical school professor and emergency room physician who became an expert on gun violence after seeing so much of its aftermath.

When it comes to gun laws, California is the exception. Magazines of more than 10 rounds are illegal here. The waiting period to buy a handgun is 10 days.

It's not known whether Loughner was ever detained because of his mental state. But in California, someone who has been held for 72 hours for observation is banned from buying a gun for five years.

There was a time when federal law, like California law, banned assault weapons and magazines that held 30 rounds.

But the law, pushed by Sen. Dianne Feinstein, expired in 2004 in George Bush's tenure. With Republicans controlling the House, there's no chance the prohibition will be revived, though Democrats will try.

Arizona state Sen. Russell Pearce was the author of the law allowing Arizona residents to carry weapons without permits legally.

"It's a freedom that poses no threat to the public," he was quoted in the Arizona press as saying when Brewer signed the bill.

Pearce's name might sound familiar. He carried the legislation requiring police to question people they suspect of being illegal immigrants about their immigration status.

No one knows yet whether there's a connection between the furor over immigration and Loughner's rampage, or any of the other overheated and hateful rhetoric of recent years.

But this is clear: A young man who clearly is mentally troubled should not be able to buy a gun and magazines that hold 30 rounds, almost no questions asked, with a waiting period that is a joke. And he certainly should not be able to walk around with it concealed, legally.