With each new terrorist attack, world leaders warn of the danger of weapons of mass destruction, which could devastate entire continents in the hands of malevolent militants.

The threat posed by unconventional weapons can't be underestimated. But those who study worldwide violence say the real and present danger is not the technically complex, expensive and hard-to-obtain nuclear, chemical and biological weapons, but small arms, which have proliferated in the past half century to kill millions of innocent people.

"Everyday terrorism is linked with small arms," says Keith Krause, program director of the Geneva-based Small Arms Survey. "Most attacks are done locally, and local people are targeted. You don't need a high degree of sophistication if you want to kill."

Small arms include not only handguns but any weapon that can be carried and fired by one person: assault rifles, automatic weapons, hand grenades, land mines, shoulder-launched missiles and small explosives.

According to British police, the London bombs that killed more than 50 commuters last week weighed less than five kilograms each, compact enough to carry in a backpack.

Small arms are portable, easy to use, and so lethal that, every two years, they annihilate 1 million people — the equivalent of a city the size of Ottawa. With the aid of small arms, thousands of women are raped, children are forced into murderous militias, and weak states crumble.

Victims in every country are intimately aware of the damage done by small arms. But, until recently, these deadly weapons have failed to capture the attention of politicians.

This week at the United Nations, delegates met to review progress on the 2001 U.N. Program of Action on Small Arms — a project backed by Canada and created to reduce the flow of illegally traded weapons to international conflict zones.

"The proliferation and misuse of small arms and light weapons exacerbate crime and conflict, undermine respect for international humanitarian law, hamper provision of humanitarian assistance, hinder economic development and interfere with conflict prevention and peace-building efforts," said Tim Martin, head of the Canadian delegation to the U.N. meeting.

More than 20 governments have now signed up to a proposed legally binding Arms Trade Treaty, which would ban arms transfers likely to fuel conflicts and human rights violations, or undermine development — an event that has given campaigners new hope that the deadly trade can be reduced if not eliminated.

But, says Amnesty International's Ottawa campaigner Hilary Homes, "the issue still isn't getting the attention it deserves. Whether in Iraq, Afghanistan or Ivory Coast, it's not weapons of mass destruction that are the problem. It's small, conventional weapons."

One of the major stumbling blocks to controlling the small arms trade is America's strong attachment to guns, and suspicion of attempts to control them, experts say.

Statistics show that the United States has 220 million guns, or almost one for every man, woman and child in the country. With less than 5 per cent of the world's population, America harbours one-third of the world's 640 million small arms.

Ryerson professor Wendy Cukier, president of the Canadian Coalition for Gun Control, says living next to the world's biggest stockpile has boosted violence among America's neighbours. "In Canada, half of the handguns used in crimes are from the U.S. In Mexico, it's 80 per cent. The fact that the U.S. has inadequate controls fuels the illicit trade in arms worldwide."

Since Canada passed gun laws in the 1990s, Cukier points out, 90 per cent of gun owners are licensed and firearms deaths have dropped by about 40 per cent. But, she says, although deaths from rifles and shotguns have dwindled, "there has been no comparable reduction in handgun violence."