I had a teacher in college who used to ask, Who discovered America? He would offer some choices. They were Amerigo Vespucci, Christopher Columbus or the Nina, the Pinta and the Santa Maria. The answer he wanted was the three ships with which eventually someone would have discovered the New World and without which everyone would have remained in Spain. It is no different with the tragedy in Tucson. Hate speech and madness were part of the mix, but it was the gun and our insane gun laws that resulted in six deaths. Until we come to grips with that, as a nation, we remain armed and dangerous.

The American culture, the American gun culture, insists on a constitutional right to bear arms - even concealed weapons such as a Glock 19 semiautomatic handgun capable of doing immense damage. A 22-year-old man, already hallucinating on the Internet, making no sense in his classes and booted from school for his strange ways, can buy such a killing device almost on the spot. If he is crazy, then so are we.

No real questions are asked of him. Do you think the government controls grammar and grammar controls the universe? Have you been babbling in class and can you hold a job? Why do you want this gun? Do you, perhaps, want to kill someone? Do you want a Glock 19 because it was one of two handguns used in the Virginia Tech massacre (32 killed, one suicide), and would you please state the name of your intended victim on the form provided? Thanks. This will just take a moment to process.

In the immediate wake of the Tucson shooting, America rounded up the usual TV posse and went in search of a reason. By mysterious consensus of the talk show zeitgeist, the supposedly rancorous political environment and Sarah Palin's use of cross hairs on her Facebook page were blamed for the shooting of Rep. Gabrielle Giffords. I am usually in favor of blaming Palin for almost anything, but this time she is not at fault. The use of cross hairs is no more menacing than the use of the word "targeted." Besides, we have no idea whether the alleged shooter, the quite addled Jared L. Loughner, even saw that posting.

Certainly, the political environment can have an effect. The demonization of a mere political opponent can sometimes give someone the license to become violent. The culture is the sea in which we all swim. Even crazy people can get the message. But we don't as yet have any idea of what message Loughner was getting. Was he out to get Giffords because she represented the oppression of government or because she is an attractive woman or because she is a Jew? The mind of a madman is a bog. It's easy to get lost.

But rather than going on a national guilt trip, we should turn our attention to the one element in this tragedy that can be controlled: easy access to guns. After all, enough ought to be enough. Rifles can kill (John F. Kennedy, for instance), but most homicides committed using firearms - more than 70 percent - are the work of handguns (Robert F. Kennedy, for instance). The handgun is wonderfully effective. It's little and it's lethal.

Gun statistics are nothing less than astonishing. According to the Brady Campaign, an advocacy group, "more Americans were killed with guns in the 18-year period between 1979 and 1997 (651,697) than were killed in battle in all wars since 1775 (650,858)." Even recognizing that some of those deaths were suicides or accidents, the gun is what did it. Had it not been handy, a death might have been avoided.

Little in life is easy or open-and-shut. There is probably no getting rid of all guns, there is no denying their appeal, and there is no use ignoring the Second Amendment. But amendments can be repealed and then reworded (long guns only?) and somehow made to conform to the 21st century. I have in the past admitted a sometime yen to have a handgun for protection - I have twice been burglarized, once while I was in the house - but my own moderate paranoia cannot make me duck the obvious. Six people are dead and 14 wounded in Arizona not just because a man went crazy or political rhetoric has gotten too raw, but because they were shot. It's the gun that did it.

cohenr@washpost.com