Many regional conflicts across the globe, particularly in Africa, are fought primarily using small arms: weapons that can be carried by one or two people and that are cheap and easy to obtain.
In Part 3 of our series on Weapons Proliferation, Amy Katz takes a closer look at these weapons, which experts say pose a larger threat than the more feared nuclear, chemical and biological "weapons of mass destruction."
When U.S.-led forces invaded the Iraqi city of Fallujah in late November they faced strong opposition from insurgents. They also found huge caches of the insurgents' small arms.
Rachel Stohl of the Washington, D.C. Center for Defense Information says the more weapons there are in a given society, the more likely it is they will be used to do harm. "So, in Iraq, for example, where there are huge weapons caches being found, the likelihood, if those weapons aren't adequately collected, secured and destroyed -- which all three of those things need to happen to eliminate them from being a threat -- those weapons can be used for crime, for violence, for intimidation against peace keepers, against troops in the field, against other citizens."
Ms. Stohl says in countries where weapons are not dealt with properly, their numbers will only continue to increase. And they will likely end up moving across borders and into other conflicts. "Small arms are so cheap, you can always find a ready supply of them, they're easily available, they're cheap, they're portable, and with them you can continue to perpetuate conflicts for years and years," she added.
Michael Krepon is the founding President of the Henry L. Stimson Center -- a Washington, D.C. institute that promotes international peace and security. He says Iraq is just one of the countries where the proliferation of small arms has become a major concern.
"I would say one half to one third the countries of Africa, we can start there. Iraq, Iran and Iran's assistance to insurgent forces in Iraq. Iraq is a huge problem.? He said and added, ?Small arms are a huge problem in Kashmir, as India and Pakistan square off there. So, the list goes on and on."
Sudan is on the list: thousands of people there have fled a conflict being fought primarily with small arms.
The violence in the Democratic Republic of Congo is fueled largely with small arms, as was the separatist war in Papua New Guinea in the 1990s.
Small arms are also responsible for much of the trouble in the Middle Eastern nation of Yemen, where there are reportedly three guns for every person.
And they were a huge problem for U.S. forces in Afghanistan. Since U.S. forces entered the country in 2001, Afghanistan has become one of several success stories on the small arms front. Many militias there have now turned their weapons over to the United Nations.
Rachel Stohl says there have been similar successes elsewhere. "There is progress being made on small arms every day. In communities in Africa, in Central America, we're seeing citizens voluntarily turning in their weapons and saying we don't want to use these weapons as our source of livelihood anymore. We want a peaceful society."
But, Michael Krepon says international action is needed to solve the problem, through conflict resolution, more than trying to stem the flow and the use of small arms. "Countries that are wracked by the use of small arms internally, need to find some internal peace with the help of outsiders. Conflict resolution is the best solution to the small arms problem."
Without a greater effort, experts say, small arms will remain the single greatest proliferation issue.
Mr. Krepon emphasized the point, "More people die from small arms than from weapons of mass destruction. This is a huge problem and a hugely difficult problem."