WASHINGTON (AP) - President Barack Obama says all of the leaders
attending a nuclear security summit have endorsed his goal of
securing nuclear materials around the world within four years.
Obama acknowledged Tuesday that the goal won't be easy.
He says, however, that the group agreed that the threat of
nuclear terrorism is among the largest challenges to global
He says the urgency of the threat brought leaders
together around his four-year goal.
Closing the session in Washington, Obama said leaders made
several specific promises to change the way nuclear materials are