Twenty-five years ago, President Reagan laid out a vision for a world without nuclear weapons, and in his first term President Obama boldly picked up that mantle -- most famously in his 2009 speech in Prague, where he announced America's commitment to eliminate all nuclear weapons globally. There is now a unique opportunity for President Obama, in his second term, to follow through on that commitment and set the world's course to global zero. He can do this by pursuing further reductions to the United States' and Russia's massive Cold War arsenals and bringing other key countries to the table for the first multilateral nuclear arms negotiations in history.

This week, Global Zero -- the international movement for the elimination of nuclear weapons -- is launching a global campaign urging President Obama to do just that. And we are calling on him to make a major announcement about this on April 5, 2013 -- the fourth anniversary of his historic Prague speech.

As part of this campaign, we are rolling out a short video narrated by my fellow Global Zero leader Michael Douglas, which is being promoted by a host of celebrities, organizations and students on social media and that we hope the president will watch.

In addition to the video, the campaign includes a letter to the president from approximately 75 former prime ministers, foreign and defense ministers and military commanders; an official declaration recently adopted by the European Parliament in support of Global Zero's step-by-step plan to eliminate nuclear weapons; and a grassroots petition appealing directly to the president.

We believe that President Obama wants to make good on his commitment to seek a world without nuclear weapons and elevate it to be a legacy issue of his presidency -- but he is facing a host of other pressing problems in the world and he needs to hear urgent support for eliminating nuclear weapons.

The Global Zero movement is supported by hundreds of respected national security and military leaders from around the world who understand that nuclear weapons do not address today's security threats -- and a powerful grassroots movement that's led by the world's first post-Cold War generation, which rejects absolutely the 20th century idea of basing national security on the threat of mass destruction.

Years from now, when the last nuclear bomb is dismantled, it will be because people all over the world had the courage to demand zero -- and a safer world for their children, their grandchildren and all generations to come. Please join this critical campaign at www.globalzero.org and join us as we call on President Obama to set the world's course to zero.

Together, we can make history....

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