World Leaders Agree to Secure Nukes in 4 Years

President Obama said all 49 leaders attending a nuclear security summit have endorsed his goal of securing nuclear materials around the world within 4 years. Obama acknowledged the goal will not be easy but said world leaders recognized the danger of nuclear terrorism. "Because of the steps we've taken...the American people will be safer and the world will be more secure," he said.

Obama also said he's confident China will join other nations in pressing for tough new sanctions on Iran over its nuclear programs. "Words have to mean something," said the president at the conclusion of the two-day gathering. "There have to be some consequences." (More President Obama stories.)