When Beatrice Fihn received a call on Oct. 6 informing the 35-year-old Swede that her group, the International Campaign to Abolish Nuclear Weapons (ICAN), had been awarded the Nobel Peace Prize, she suspected a possible prank. Not that you should blame her - ICAN is just 10 years old, and the group's aims can seem positively fanciful: the complete elimination of the world's roughly 15,000 nuclear warheads. But that call from the Norwegian Nobel Committee was real, and so is Fihn's goal. ICAN, a global coalition of 440 partner organizations in 98 countries, was honored for its efforts to advance the Treaty on the Prohibition of Nuclear Weapons, which was successfully finalized by two-thirds of the United Nations' 192 members this summer. The treaty-which would outlaw nuclear weapons' use, production and possession-is now open for ratification, and will become international law after 50 countries sign on. Those countries almost certainly won't include the members of the nuclear club: The U.S., Russia, China, Great Britain, France, Pakistan, India and North Korea. Fihn is realistic that nuclear weapons won't be abolished overnight. But just as earlier treaties banning biological weapons and land mines eventually led to such munitions being phased out, she believes a nuclear arms ban could help turn the public against these truly horrific weapons of mass destruction.