Dozens of world leaders gather in Washington next week for an unprecedented meeting on nuclear security, with U.S. President Barack Obama hoping they can agree on how to keep atomic bombs out of terrorists’ hands.

Although the gathering of 47 countries will not focus on individual nations, the nuclear programs of Iran and North Korea — and possible new U.N. sanctions against Tehran — are expected to come up in Obama’s bilateral meetings with Chinese President Hu Jintao and other leaders, as well as in the speeches of Israeli and other participants.

Hu’s decision to attend the summit, Western diplomats said, was a major victory for Obama, since it indicates that Beijing does not want bilateral tensions over Taiwan and other issues to cripple Sino-U.S. relations and cooperation on other key security and foreign policy topics.

A draft communique circulated to countries attending the summit, the contents of which were described to Reuters, includes a U.S. proposal to “secure all vulnerable nuclear material in four years.” The draft text will likely be revised before it is adopted at the end of the April 12-13 meeting.

Analysts and Western diplomats say the significance of the summit meeting — one of the biggest of its kind in Washington since World War Two — goes far beyond its official agenda.

“Too many people see nuclear security as a narrow technical issue of concern only to those most fearful of nuclear terrorism,” Ian Kearns of British American Security Information Council said in a report.

“If leaders at the summit get it right, they could render nuclear power safer to use in the fight against climate change, strengthen the non-proliferation regime, and build further international confidence in … nuclear disarmament,” said Kearns, who is an adviser to Britain’s parliamentary committee on national security.

In addition to China’s Hu, attendees include Russian President Dmitry Medvedev, French President Nicolas Sarkozy and German Chancellor Angela Merkel.

Also represented will be India and Pakistan, which never signed the 1970 nuclear Non-Proliferation Treaty but have atomic arsenals, and Israel, another NPT holdout that is presumed to have atomic weapons but has never confirmed it.

NO INVITATIONS FOR IRAN, NORTH KOREA

The inclusion of Pakistan, diplomats say, is important since it is one of the countries that has pledged to improve its internal safeguards. Disgraced Pakistani scientist Abdul Qadeer Khan was the kingpin of an illicit atomic network that provided atomic technology to Iran, North Korea and Libya.

Two nations excluded from the meeting are Iran, which the United States and its Western allies accuse of pursuing nuclear weapons, and North Korea, which withdrew from the NPT in 2003 and has twice detonated nuclear devices despite its promise to abandon its atomic programs. Both are under U.N. sanctions.

Joe Cirincione, a professor at Georgetown University and head of the Ploughshares Fund anti-nuclear arms group, said the plan to secure nuclear materials worldwide within four years could substantially boost global security.

“If they follow through, this strategy could effectively prevent nuclear terrorism by stopping radicals from getting the one part of the bomb they cannot make themselves,” he said.

But Cirincione wants to see if the final communique is “more than a 2-page press release, if the action plan has real targets and real deadlines, if key nations pledge to secure their weapons material within four years, and if the states agree to meet again in two years to assess progress.”

On the agenda are plans to join together a disparate group of countries with nuclear programs to gather up dangerous atomic material from vulnerable nuclear, defense and medical sites worldwide, something Russia and the United States have been doing with the aid of the U.N. atomic watchdog for years.

If successful, the summit can send a strong signal to the world that the international community is united in boosting nuclear security and that Washington is taking a leading role.

The White House on Tuesday unveiled a new policy that restricts U.S. use of nuclear weapons, while sending a stern warning to Iran and North Korea that they remain potential targets. Reversing the position of the former U.S. administration, the so-called Nuclear Posture Review also said Washington would not develop any new atomic weapons.

Analysts said the combination of the U.S. nuclear policy, the success of Obama and Medvedev in agreeing a new treaty committing them to reducing their atomic arsenals, and a productive nuclear summit could help set the stage for a successful gathering of NPT signatories in New York next month to find ways to overhaul the 40-year-old arms pact.

Analysts say the NPT has been battered by North Korea’s withdrawal, Iran’s insistence on pursing nuclear technology that could help it make bombs and developing nations’ charges that big nuclear powers are ignoring disarmament commitments.

Possible new U.N. sanctions against Iran over its nuclear program will be the focus of a Thursday meeting of envoys from the United States, Britain, France, Germany, China and Russia in New York. U.N. diplomats said their leaders were ready to discuss Iran on the sidelines of the summit if Obama wants to.

The four Western powers have persuaded China and Russia to help draft a fourth U.N. sanctions resolution against Tehran for refusing to suspend its nuclear enrichment program. Iran rejects Western allegations that its atomic program is aimed at developing weapons and refuses to stop enriching uranium.

(Editing by Mohammad Zargham)