(CNN) -- President Barack Obama followed in the footsteps of past U.S. leaders with a speech on Wednesday at Berlin's iconic Brandenburg Gate, where he said he would ask Russia to join the United States in slashing its supply of strategic nuclear warheads. "We may no longer live in fear of global annihilation, but so long as nuclear weapons exist, we are not truly safe," Obama said in the city that symbolized the East-West divide in the decades after World War II. "After a comprehensive review, I've determined that we can ensure the security of America and our allies -- and maintain a strong and credible strategic deterrent -- while reducing our deployed strategic nuclear weapons by up to one-third," he said. "And I intend to seek negotiated cuts with Russia to move beyond Cold War nuclear postures."
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NEW: Historian calls Obama's speech good, but not a "gold star" in history
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President Obama says it's time to "move beyond Cold War postures" on nuclear arms
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Obama invokes JFK's "peace with justice" call from 50 years ago
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The president speaks at Berlin's iconic Brandenburg Gate
He also quoted from @placeholder's speech by calling on people to look "to the day of peace with justice, beyond yourselves and ourselves to all mankind."