Vienna, Austria ? China has them. The United States, Britain, France and Russia have them. So do India and Pakistan. Israel likely does, and North Korea may be trying to get them.

Nuclear weapons abound, in friendly and unfriendly hands. So why is Washington singling out Iraq in its post-Sept. 11 crusade to purge the world of the threat?

The obvious explanation: Saddam Hussein who has used chemical weapons against neighboring Iran and his own people refuses to let U.N. weapons inspectors return to check intelligence reports that he may be trying to build a nuclear bomb.

But as President Bush ratchets up his quest for support for an invasion of Iraq, agencies monitoring the global proliferation of weapons of mass destruction say a regime change in Baghdad won’t eliminate the menace posed by other unpredictable governments.

“There’s always a worry when one country is focused on that others will be ignored, and that’s a mistake,” said David Albright, a former Iraq weapons inspector who runs the Washington-based Institute for Science and International Security.

“There are serious problems in South Asia that aren’t getting addressed, and the Bush administration isn’t reaching out at all to Iran,” he said. “These situations are very dangerous and require a lot of attention. If everybody’s looking at Iraq, it’s more difficult to come up with an overall engagement strategy.”

Plenty of threats

The Federation of American Scientists, which keeps tabs on nuclear arms worldwide, offers a bleak assessment of the global threat:

l At least 17 countries either have nuclear weapons or are believed, based on Western intelligence, to have the means to produce them. Seven nations have confirmed nuclear arsenals: Britain, China, France, India, Pakistan, Russia and the United States. Israel, which is reported to have up to 100 warheads, has never confirmed its arsenal. Countries suspected of pursuing nuclear weapons include Iran, Iraq, Libya and North Korea.

l Nineteen countries are suspected of having or pursuing biological and chemical weapons. They include Egypt, India, Iran, Iraq, Israel, Laos, Libya, North Korea, Pakistan, Russia, South Africa, Syria and Taiwan. The United States had a biological weapons program from 1942 to 1969 and had 30,000 tons of chemical weapons in 1997 when it pledged to destroy the stockpile within 10 years.

l Sixteen nations have the missile technology capable of carrying nuclear, biological or chemical weapons to distant targets. Aside from major nuclear powers, they include Egypt, India, Iran, Iraq, Libya, North Korea, Pakistan and Syria.

Thirty-two countries produce more than 150 different kinds of unmanned drone aircraft capable of flying undetected below missile-defense systems to deliver a nuclear or biological payload, the Carnegie Endowment for International Peace says in a new book, “Deadly Arsenals: Tracking Weapons of Mass Destruction.”

Iraq, whose military was decimated by the Gulf War, likely doesn’t have nuclear weaponry, despite the Bush administration’s insistence that Baghdad is working to acquire the technology.

The respected International Institute for Strategic Studies said in a report this week that although Baghdad has substantial supplies of chemical and biological agents, a nuclear bomb could be years out of its reach. It hastened to add, however, that Iraq could build a bomb “in a matter of months” if it obtained high-grade radioactive material.

Iraq stands apart

Is the fuss over Iraq obscuring the broader fight to contain the nuclear, chemical and biological threat? Dennis M. Gormley, a senior fellow at the London-based institute, doesn’t think so.

“There’s a decided difference between Iraq and the other members of the so-called ‘axis of evil,”‘ Gormley said. “There’s a track record of irresponsibility on Iraq’s part. For 11 years, Iraq has flouted 16 U.N. Security Council resolutions. Iraq has used chemical weapons against its own population and against one of its neighbors, Iran.”

During the 1980-1988 Iran-Iraq War, Iraqi forces used chemical weapons numerous times. U.N. investigators confirmed the use of two main Western-made formulas: mustard gas and a nerve gas.

In 1988, Saddam’s military bombed the Iraqi town of Halabja with poison gas to put down Kurdish rebels, killing an estimated 5,000 people.

“In a sense, we have this narrow window of opportunity to do something about what can only become worse,” Gormley said. “This may be our last best chance.”