ROBERT SIEGEL, HOST:
This is ALL THINGS CONSIDERED from NPR News. I'm Robert Siegel.
AUDIE CORNISH, HOST:
And I'm Audie Cornish. You are holding a gun against Iran, saying talk or you'll fire - so reads a statement issued today by Iran's Supreme Leader Ayatollah Ali Khamenei. It comes in response to a speech earlier this week from Vice President Joe Biden suggesting the U.S. would be open to direct talks with Iran over its nuclear ambitions.
SIEGEL: The Supreme Leader's answer, in short, talks will not solve any problems. Iran's President Mahmoud Ahmadinejad echoed that sentiment later in the day while visiting Cairo. He made clear that his government has no interest in direct talks until the U.S. eases sanctions that have been suffocating Iran's economy.
CORNISH: But the Obama administration isn't budging. This afternoon, State Department spokeswoman Victoria Nuland said the ball is in the Iranian's own court.
VICTORIA NULAND: The burden of these sanctions could be eased if they made a decision to engage with us substantively. We've always said that action on the Iranian side would be matched by action on our side. So it's really up to Iran to engage if it wants to see sanctions eased.
SIEGEL: The suspicion that Iran wants to make a nuclear weapon is, of course, the rationale for those tough sanctions, as well as for veiled threats of U.S. or Israeli military action if those sanctions fail to persuade. It's also the subject of a global effort that keeps popping up in the news every few weeks, a game of nuclear keepaway, an effort to keep Iran from buying or making the machines that make uranium suitable for a bomb - centrifuges.
DAVID ALBRIGHT: We call it the long pole in the tent. Getting the wherewithal to make the weapon-grade uranium is harder than learning how and assembling everything you need to make the nuclear weapon itself.
SIEGEL: That's David Albright. He's a physicist and a former U.N. inspector. Most uranium is useless for nuclear fuel or weapons. Less than 1 percent is the light radioactive isotope U235. But gasify uranium with fluorine, put it in a centrifuge, and as Professor Houston Wood of the University of Virginia explains, you can separate the nuclear wheat from the chaff.
HOUSTON WOOD: The centrifuge is spinning very rapidly and then the gas will spin at the same speed as the wall is spinning, and the heavier isotope, uranium 238 will tend to move towards the wall and the lighter isotope will tend to move towards the axis. And then you remove uranium that has been enriched in uranium 235 and the other stream is depleted in uranium 235.
SIEGEL: Houston Wood, who worked on gas centrifuges at the U.S. Department of Energy, is talking about a very slight degree in enrichment when you do that. But if you take the stuff that has more U235 and do this over and over and over again, eventually, you can get uranium that is 90 percent U235, weapons-grade uranium. That takes thousands of centrifuges arranged in what's called a cascade.
David Albright says the Iranians started shopping for the parts to do all this as early as 1985.
ALBRIGHT: It's when they first showed up in Europe looking to buy equipment and their philosophy at the time was let's go buy what we need. They went out and bought all kinds of equipment in Europe.
SIEGEL: But they couldn't make it work. In the early 1990s, Albright says, they turned to A.Q. Khan, the European-trained physicist who had made Pakistan's bomb.
ALBRIGHT: And they decided to just go out and buy 500 of what were called these P1 centrifuges from the Khan network.
SIEGEL: P is for Pakistan. Over the years, Iran has told the International Atomic Energy Agency that with the centrifuges it has, it has enriched uranium to the 5 percent level, that's low enriched uranium, to make fuel for a nuclear power plant. They also reported enriching some uranium to 20 percent, which they say is for a research reactor.
And according to a recent AP story, they evidently intend to enrich more uranium to that level. They have never said they intend to go for 90 percent. But it shouldn't be that hard. It takes far more effort to get to 20 percent enrichment from less than 1 percent than it would take to go from 20 percent to 90 percent. The way you enrich more uranium is to have more centrifuges and also to make them go faster.
Professor Houston Woods says how fast depends on what they're made of.
WOOD: If you make them out of aluminum, they can only go to about 350 meters per second and that's because if you spin it faster, the metal will just burst. And there's another material called maraging steel and that can be used to make centrifuges and it can go up to about 450 meters per second. And after that, there are composite materials like carbon fiber that are used to make centrifuges. And the limit on that is 1,000 meters per second.
SIEGEL: So part of the game of keep-away has been trying to block Iran from getting these highly specialized materials with which they could make centrifuges spin faster. Houston Wood mentioned maraging steel, a steel that is hardened with nickel and other metals. David Albright says the Iranians went shopping for it in Britain.
ALBRIGHT: Iran successfully bought 70 tons of maraging steel, enough in theory for over 30,000 centrifuges, from Britain in the 1990s. The Brits caught them eventually and kept them from buying more.
SIEGEL: According to the U.S. Department of Justice, the Iranians are still shopping for maraging steel. Prosecutor Steve Pelak says one of the hottest cases the department has brought involves an Iranian named Parviz Khaki. He tried to buy 20 tons of the maraging steel, allegedly with the help of a Chinese citizen. Last July, the two were indicted.
STEVEN PELAK: The goods were maraging steel and other devices that can be used in many, many common uses in the scientific communities. But we knew from the initial calls to the company that something just didn't make sense.
SIEGEL: In particular, the Chinese company that was trying to buy the strengthened steel in the U.S. was a toy company.
PELAK: Toy companies don't need 20 tons of maraging steel, which is very, very expensive.
SIEGEL: That would make one hell of an Erector set. The case against Parvis Khaki, who was arrested in the Philippines and remains in custody there fighting extradition to the U.S., reveals an interesting fact about the game of nuclear keep away. Justice Department officials say Khaki found that Chinese maraging steel was shoddy. The good stuff is made here, but shopping for it in the U.S., you find yourself in a pretty small market.
PELAK: The companies that make and sell these goods legitimately, they know who their customers are. They know who's buying things and why. So when they're approached by somebody that's out of left field that just doesn't make sense.
SIEGEL: In this case, the company tipped off the government and prosecutors set up a sting operation. Centrifuges made of carbon fiber spin even faster than maraging steel, but David Albright say they also pose problems.
ALBRIGHT: When you use carbon fiber in the rotor, I mean, it involves winding this very strong fiber around, it's called a mandrill, just a cylinder. And it's hard to figure out what pattern to use.
SIEGEL: And before you even wind the carbon fiber, somebody has to make it.
ZSOLT RUMY: Making carbon fiber is just kind of like sex. You can read about it and talk about it all you can, but you don't know what it's like until you actually do it.
SIEGEL: That's Zsolt Rumy, who runs a company called Zoltek in St. Louis that makes carbon fiber. Zoltek has nothing to do with this case, but Rumy told me about this product that can be used to make such fast-spinning centrifuges and also it can be used to make golf club shafts and bicycle frames. Once again, it's a specialized industry and people know people.
RUMY: We know our customers because applying carbon fibers and using it in various processes is difficult.
SIEGEL: In December, the Justice Department busted an Iranian-American named Reza Hamid Hashemi when he stepped off a plane in New York. The U.S. says Hashemi had been working through a Turkish partner, shopping for carbon fiber in the U.S. He was interested in a type of fiber called IM7, that's used mostly by aerospace companies, but it's also advertised for centrifuges for nuclear enrichment.
Hashemi has refused to comment through his lawyer. He allegedly came to the U.S. to see a carbon fiber winding machine and that turned out to be another sting. The global game of nuclear keep-away has gotten a lot easier with the new U.N. sanctions against Iran, but how successful can the U.S. really be at keeping these specialized products out of hands it deems dangerous?
I asked David Albright: Who's favored to win in this game of keep-away; the would-be nuclear proliferator or the anti-proliferation effort?
With export controls, the proliferator. In the case of Iran, with the U.N. Security Council resolutions that made it easier to police this, I think it's 50/50. And what you see is Iran's procurements are often detected and stopped; there interdictions of nuclear related items. What you're trying to do is buy time. You want to limit the numbers that they can build so you can delay their program. But you can't stop it.
Which is one reason we're hearing a lot about the alternatives to nuclear keep-away: diplomacy, sanctions and the threat of force. And we're likely to hear a lot more about all of the above in the coming months.
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