PRAQUE, Czech Republic — For half a century, American presidents have talked about easing or eliminating the threat of nuclear annihilation while maintaining an arsenal at the core of U.S. defense strategy.
On Sunday, President Barack Obama committed the United States to a long-term goal of ridding itself and the world of nuclear weapons and said his first step would be to downplay the United States' nuclear weapons as the keystone of its defense.
"Today, I state clearly and with conviction America's commitment to seek the peace and security of a world without nuclear weapons," he said to cheers from an audience of 20,000.
"This goal will not be reached quickly, perhaps not in my lifetime. It will take patience and persistence," he said.
Obama spelled out a broad three-part plan:
_ Changing U.S. nuclear strategy and working with Russia to further slash their stockpiles of warheads.
_ Working to control the spread of weapons, including creating an international fuel bank to let non-nuclear powers get materials needed for nuclear power without developing the capacity to create material for weapons, as is feared in Iran.
_ Starting a new international effort to secure from terrorists all the materials needed for nuclear weapons.
As if to underscore the threat of attack from any corner, North Korea hours earlier launched a missile that drew international condemnation and sent the United Nations Security Council into session.
Obama had long scheduled the speech on his broad vision for cutting and eliminating the nuclear threat. But he admitted the expected North Korean launch underscored his message, first to maintain a U.S. nuclear deterrent as long as anyone poses a threat but then to rid of the world of the threat altogether.
"This morning, we were reminded again why we need a new and more rigorous approach to address this threat. North Korea broke the rules once more by testing a rocket that could be used for a long-range missile," he said.
"This provocation underscores the need for action, not just ... at the UN Security Council but in our determination to prevent the spread of these weapons," he said. "Rules must be binding. Violations must be punished. Words must mean something."
Aides said they woke Obama shortly after the launch was confirmed at 4:30 a.m. Praque time, and that he consulted with military and intelligence advisers through the morning.
White House Press Secretary Robert Gibbs declined to say whether the U.S. military had been on alert in anticipation of the launch.
"Had at any moment we determined that this launch posed a threat to the United States of America, we would have taken whatever steps were necessary to ensure the safety and security of the American people," Gibbs said.
He also declined to say whether the United States had any information to confirm or deny North Korea's claim that the missile merely launched a satellite and was not a test of a long-range rocket.
Fraught with symbolism, Obama chose to deliver the speech in a city that once tried bravely to defy Soviet oppression in 1968 and where, he said, the Velvet Revolution overthrowing Communist rule in 1989 "proved that moral leadership is more powerful than any weapon."
And he spoke in the center of a Europe so often divided by war but now "peaceful, united and free because ordinary people believed that divisions could be bridged, that walls could come down; and that peace could prevail."
Obama stressed that the United States will "maintain a safe, secure and effective arsenal to deter any adversary" as long as nuclear weapons exist. But he insisted that the United States will "begin the work of reducing our arsenal."
He echoed his earlier announcement that the United States and Russia will work to negotiate a new treaty this year cutting their nuclear arsenals.
Also, he said he will immediately push for U.S. ratification of the Comprehensive Test Ban Treaty.
"After more than five decades of talks, it is time for the testing of nuclear weapons to finally be banned," he said.
On another front, Obama said he'll work to stop the spread of weapons to non-nuclear countries, by pursuing a new treaty to end the production of fissile materials intended for use in weapons.
"If we are serious about stopping the spread of these weapons, then we should put an end to the dedicated production of weapons-grade materials that create them," he said.
He'll also try to strengthen the nuclear Non-Proliferation Treaty with more international inspections and with "real and immediate consequences" for those that break the rules.
"We go forward with no illusions," he said. "Some will break the rules, but that is why we need a structure in place that ensures that when any nation does, they will face consequences."
Turning to another potential nuclear threat, Obama said flatly that "Iran has yet to build a nuclear weapon." He said he will seek engagement with Iran and offer Iran a clear choice between a nuclear energy program with "rigorous inspections" or "increased isolation, international pressure, and a potential nuclear arms race in the region."
In the meantime, he said, Iran remains a threat and still warrants plans for a controversial missile defense in central Europe.
"As long as the threat from Iran persists, we intend to go forward with a missile defense system that is cost-effective and proven," he said as anti-missile defense protestors stood vigil near the square.
"If the Iranian threat is eliminated, we will have a stronger basis for security, and the driving force for missile defense construction in Europe at this time will be removed," he said.
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