Iran repeatedly cites Article 4 of the Nuclear Nonproliferation Treaty (NPT), which asserts the "inalienable right" of all parties to the treaty to develop and use nuclear energy. It refuses to shut down its nuclear-fuel program, despite offers of economic incentives from three European powers.
A powerful Iranian official and former president, Ayatollah Ali-Akbar Hashemi-Rafsanjani, reaffirmed Tehran's intentions on 29 April. "Iran wants to have [uranium] enrichment and all branches of nuclear technology because Iran wants to be able to use the benefits of this very valuable field of science for its people and we will do it by any price," he said.
But the United States is worried that Iran's nuclear ambitions will leave what it calls the world's leading state sponsor of terror free to develop and traffic nuclear weapons.
Some experts say more worrisome than the risk of Iran using weapons is the possibility it could trigger a regional nuclear arms race. This concern is already evident in the refusal of three nearby countries to join the NPT -- Israel, Pakistan, and India.
Similarly, North Korea's withdrawal from the treaty and efforts to develop nuclear weapons have contributed to nuclear tensions in East Asia.
U.S. officials at the conference will press President George W. Bush's call for the world's leading nuclear exporters to condition access to nuclear fuel for other states on their renunciation of enrichment and reprocessing. Facilities capable of uranium enrichment can also produce material for nuclear weapons.
Iran has stressed its peaceful intent. But U.S. Assistant Secretary of State Stephen Rademaker told lawmakers last week that concerns over Iran's long-concealed program will generate much debate this month.
"Iran will be a major subtext of all of the discussions that take place in New York. I'm not sure how much the discussions will in the first instance be about Iran -- in other words, how often delegations in their presentations will mention the word Iran -- but the subtext in much of the conversations will be Iran," Rademaker said.
Nuclear experts say the 35-year-old NPT has generally succeed in limiting the development of nuclear weapons. But they point to several flaws that risk unraveling the treaty.
One is interpretation of the "inalienable right" clause. That article also calls on states to develop nuclear energy "in conformity" with the treaty's nonproliferation provisions. Article 2 stipulates that nonweapons states are not to seek or receive any assistance in the manufacture of nuclear weapons. It also requires these states to place all of their civil nuclear activities under the safeguards of the International Atomic Energy Agency.
But this language has been long neglected by treaty monitors, says Henry Sokolski, a former U.S. Defense Department arms-control official who gave testimony to a U.S. Congressional committee last week. "That anyone intended that you could get right up to the last whisker to a bomb under the treaty as a matter of right strikes me as absolutely insane and I don't think the people who drafted this were insane," he said.
Despite proliferation concerns, Rademaker expects Iran to receive support in New York from non-nuclear states who oppose giving up the right to high technology. A number of non-nuclear states also use treaty review conferences to press the five major nuclear powers to honor commitments to reduce their nuclear stockpiles.
Rademaker told the U.S. Congress last week that the U.S. disarmament record was excellent and that Washington planned no major concessions to induce cooperation on nonproliferation matters. "This notion that the United States needs to make concessions in order to encourage the preservation of the nuclear nonproliferation regime is, I believe, at best a misguided way to think about the problems confronting us," he said. "Basically, it establishes a rationalization for Iran's noncompliance."
The United States has reduced its nuclear stockpile by more than 13,000 weapons since 1988. But the United States and Russia between them have 28,000 nuclear warheads. Causing new concerns are requests by the Bush administration for funding to research new kinds of nuclear weapons.
Charles Ferguson, an expert on nuclear arms at the independent Council on Foreign Relations, says the administration needs to take further steps to reduce its nuclear arsenal as a confidence-building measure.
"We need to decide exactly how many weapons do we really need and find a way to adjust our nuclear posture so it doesn't look threatening to Russia, doesn't look threatening to China. We still maintain a nuclear deterrent posture and we also take a new look at how the path we're going down to possible new nuclear weapons may affect other nations."
Just days before the treaty review conference at the United Nations, there remained no consensus on the agenda. This week will be dominated by speeches from top UN officials and high-level delegates. It was not immediately clear when U.S. Secretary of State Condoleezza Rice would attend the conference.