The Obama administration has continued to pursue a treaty to curb fissile materials that can be used in nuclear weapons, but the world -- or most importantly, one key nation, Pakistan -- isn't going along.

During the 2008 presidential campaign, then-candidate Barack Obama promised to "lead a global effort to negotiate a verifiable treaty ending the production of fissile materials for weapons purposes."
   
Fissile materials -- mainly highly enriched uranium and plutonium isotopes -- are capable of sustaining the chemical reactions necessary to create a nuclear explosion. Banning the production of additional fissile materials wouldn't prevent states from developing additional weapons -- each of the five "official" nuclear powers (the United States, Russia, France, the United Kingdom and China) still has large stockpiles, even if they have stopped producing fissile materials. Meanwhile, the rogue nuclear nations of Pakistan, India, North Korea, Iran and possibly Israel all continue to produce bomb-making material, but their reserves are much smaller, making them unlikely candidates to join the treaty.
   
Still, a proposed agreement known as the Fissile Material Cutoff Treaty would make it more difficult for nations to join the nuclear club.
   
As we noted in our previous update, the idea for an agreement on fissile materials has been around more more than half a century, but the process of actually designing a treaty began in the mid-1990s under the auspices of the United Nations' Conference on Disarmament. Obama has at least twice reiterated the need for a treaty, noting in a 2009 speech in Prague that the world needs a treaty that "verifiably ends the production of fissile materials intended for use in state nuclear weapons."
   
The process that the 65 participating nations agreed to is based on consensus. Pakistan, by most accounts, is the biggest stumbling block.

"The main barrier to negotiations has been Pakistan's opposition, due to its concerns about India's superior fissile material and nuclear weapons stockpile," said Kingston Reif, the director of nuclear non-proliferation at the Center for Arms Control and Non-Proliferation.

On Oct. 10, 2012, Rose Gottemoeller, the acting undersecretary of state for arms control and international security, said in a speech at the United Nations General Assembly that the Conference on Disarmament "remains our preferred venue for negotiating" a fissile-materials treaty, "since it includes every major nuclear-capable state and operates by consensus, ensuring everyone's national security concerns are protected."

Tacitly acknowledging the diplomatic gridlock, Gottemoeller added that "our patience on this issue is not infinite. ... We will work hard to convince others that commencement of negotiations is not something to fear."

As we noted in our previous update, we recognize that the United States has been devoting significant attention to this issue. Still, after four years in office, the Obama administration has failed to break the deadlock and get the parties to begin hammering out a treaty. So we're moving this to Promise Broken.