Breaking: Moment of Silence for Poles, Obama Announces Next Nuke Security Summit in S. Korea

President Obama led representatives of 47 nations at the international Nuclear Security Summit in a moment of silence to mourn the death of Polish President Lech Kaczynski. Obama also announced South Korea, rival to North Korea and its bedeviling nuclear weapons program, will host the next nuclear security summit in 2012.

The United Nations, the U.S. and a handful of other countries including China, South Korea and Japan have tried but failed for years to coax the reclusive Communist North Korea to give up its nuclear weapons in exchange for stronger financial support, trade, help with a civilian nuclear program and humanitarian aid. North Korea has refused or betrayed agreements to halt its production of weapons-grade nuclear material.

North Korea was not invited to the nuclear summit. It withdrew from the Nuclear Non-Proliferation Treaty in 2003. In April 2009, the International Atomic Energy Agency agreed with a North Korean announcement that it had become a "fully fledged nuclear power."

Choosing South Korea as the host of the next summit is an unmistakable signal to North Korea that its methods are likely to come under even greater scrutiny as the international community concentrates on monitoring the visibility, storage, and shipment of nuclear materials.

In discussing the massive loss of life to Poland's current government, Obama said he wanted the international assemblage to "acknowledge the terrible tragedy that struck Polish people."

Obama acknowledged Poland's ambassador to the U.S., Robert Kupiecki. Originally, Prime Minister Donald Tusk was to have represented Poland at the nuclear security summit. Tusk remained in Poland to cope with a nation in mourning and is likely to see his influence in the Polish government expand. Kaczynski and his Law and Justice Party led the opposition to Tusk and his ruling Civic Platform's pro-market, pro European Union agenda. Polish law has made parliamentary speaker Sejm Bronislaw Komorowski acting president until a special election is held by the end of June.

Obama said the world was "shocked and saddened" by the death of Poland's First Family, calling it a "loss not just for Poland, but the world," adding the United States "stands with Poland and Poles everywhere."

In prepared remarks opening the plenary session here, Obama noted what he called the great irony of the post-Cold War era: "the risk of a nuclear confrontation between nations has gone down, but the risk of nuclear attack has gone up."

Obama said highly enriched uranium or weapons-grade plutonium - the two fissile materials that can make a nuclear bomb - exist in dozens of nations across the globe. Small amounts, no bigger than the size of an apple Obama said,  "could kill and injure hundreds of thousands of innocent people."

"Terrorist networks such as Al Qaeda have tried to acquire the material for a nuclear weapon," Obama said. "If they ever succeed, they would surely use it. Were they to do so, it would be a catastrophe for the world."

Obama called the plenary session - which is pre-determined to yield a non-binding communique on new steps to securely house, monitor, and ship loose nuclear materials - is the place "not simply to talk, but to act."

"It requires a new mindset," Obama said. "That we summon the will, as nations, as partners, to do what this moment in history demands. It is increasingly clear the danger of nuclear terrorism is one of the greatest threats to our global security."

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