WASHINGTON (CN) - President Obama called on world leaders "not simply to talk, but to act" to reduce the risk of nuclear terrorism by securing vulnerable nuclear materials. "In short, it is increasingly clear that the danger of nuclear terrorism is one of the greatest threats to global security -- to our collective security," Obama said Tuesday at the 47-nation Nuclear Security Summit.
"Two decades after the end of the Cold War, we face a cruel irony of history," Obama said in his opening speech Tuesday. "The risk of a nuclear confrontation between nations has gone down, but the risk of nuclear attack has gone up."
Obama's speech opened the second day of the summit, the largest gathering of world leaders in the United States in 65 years. The summit has already seen two major successes toward nuclear nonproliferation: Ukraine's promise to rid the country of enriched uranium stores and China's decision to back the United States in sanctions against Iran.
After meeting with Obama yesterday, Ukrainian President Viktor Yanukovych announced the country's decision to get rid of all its enriched uranium stores by 2012, the date of the next nuclear summit, which will be held in Korea. Ukraine pledged to get rid of most of the nuclear material this year.
Chinese President Hu Jintao announced yesterday that China would work with the United States to establish sanctions against Iran to discourage the country from developing a nuclear weapons program.
Obama is hosting a string of bilateral meetings during the conference to secure similar commitments from other countries. The president has stated that his goal for the summit is to obtain commitments from countries to take "specific and concrete actions" to keep nuclear weapons out of the hands of terrorists.
"Terrorist networks such as al-Qaida have tried to acquire the material for a nuclear weapon, and if they ever succeed, they would surely use it," Obama said. "Were they to do so, it would be a catastrophe for the world."
He called on participating countries "to secure the nuclear materials in our countries and to prevent illicit trafficking and smuggling." Part of Obama's platform involves securing all the world's nuclear weapons within four years.
He said the summit shows a "serious and sustained effort" on the part of the international community to deal with the growing threat of nuclear terrorism.
"For the sake of our common security, for the sake of our survival, we cannot drift. We need a new manner of thinking -- and action. That is the challenge before us. And I thank all of you for being here to confront that challenge together, in partnership," Obama said.
The summit is the largest meeting of world leaders called by a U.S. president since President Franklin Roosevelt called the meeting that formed the United Nations in 1945.
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