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North Korea's missile launch took place on the same day as a very different kind of launch, a new initiative aimed at avoiding precisely the kind of nuclear weapons program North Korea is pursuing. NPR's David Welna reports on a nuclear fuel bank financed in large part by Warren Buffett. It made its debut today in Kazakhstan.

DAVID WELNA, BYLINE: This is a peculiar bank. Its only deposits are some 90 metric tons of low-enriched uranium, the kind of fuel used by most nuclear power plants. It's located in the north of Kazakhstan, the world's top source of uranium. And it's both owned and operated by the International Atomic Energy Agency. But about a third of its funding - $50 million - comes from the man widely known as the Oracle of Omaha.

WARREN BUFFETT: This is an investment in humanity. You can't roll the dice on humanity's survival.

WELNA: Speaking on the phone from Omaha, Warren Buffett says he sank some of his large fortune into the uranium fuel bank being launched today with this hope - that its promise of an uninterrupted nuclear fuel supply would discourage countries from developing their own uranium enrichment programs.

BUFFETT: I'm in insurance business among other businesses, and very, very, very tiny probabilities add up over time into something that becomes close to a certainty. And to the extent that money can be helpful in reducing that threat even by a slight margin, I think it's a very good use of funds.

WELNA: Buffett is the only private contributor. The rest of the financing came from governments including the U.S. Buffett credits former U.S. Senator Sam Nunn with coming up a dozen years ago with the idea of a nuclear fuel bank not controlled by any one nation. Nunn himself says it's all about nuclear nonproliferation, and that means keeping other nations from making their own nuclear fuel.

SAM NUNN: If a country develops the technical capability to enrich low-enriched uranium for a nuclear power plant, it can also make high-enriched uranium for a nuclear weapon. The technology is basically the same.

WELNA: Whether this nuclear fuel bank would actually supply other nations, one top nonproliferation expert says, is beside the point.

MATTHEW BUNN: I think it can have a positive effect even if no one ever takes out any of the fuel from the bank.

WELNA: That's Matthew Bunn, who's with Harvard University's Belfer Center. The bank's main virtue, Bunn says, is that with it, countries can no longer justify having uranium enrichment facilities as a hedge against having their fuel supplies cut off.

BUNN: And it makes it easier for countries like the United States to argue if some country is building its own enrichment supply that that's not really legitimate, that they don't really need it for any purpose other than giving themselves an option to build nuclear weapons.

WELNA: The fuel bank was originally conceived to discourage countries like Iran from enriching uranium. It's too late for that to happen with Iran but perhaps not for other countries with nuclear ambitions. Former Energy Secretary Ernest Moniz now heads the Nuclear Threat Initiative. He says this fuel bank's been a longtime coming.

ERNEST MONIZ: This was quite a bit of diplomacy to get all of this to come together.

WELNA: Key to that was getting transit agreements from both Russia and China, allowing deposits of low enriched uranium to be shipped over their territory to the bank and landlocked Kazakhstan. All that, says former Senator Nunn, is auspicious for reigning in nuclear threats.

NUNN: We are in a race between cooperation and catastrophe. And I would say that cooperation hasn't been running very fast. But this is a big step on the cooperation side.

WELNA: Nine nations including North Korea now have nuclear weapons. The aim, Nunn says, is to keep that number from rising. David Welna, NPR News, Washington.

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