Iranian Nuclear Expert Killed; Tensions Mount

AUDIE CORNISH, HOST: This is ALL THINGS CONSIDERED from NPR News. I'm Audie Cornish.

MELISSA BLOCK, HOST: And I'm Melissa Block. Another Iranian nuclear scientist was killed today in an explosion while driving his car. It's the fifth such death in five years, and Iranian officials immediately blamed Israel. It's also the latest sign of escalating tensions between Iran and the West. From Istanbul, NPR's Peter Kenyon looks at whether relations can only get worse or if there's still time for diplomacy.

PETER KENYON, BYLINE: Television footage showed the street where engineer Mostafa Ahmadi Roshan's life ended, in much the same manner as other nuclear scientists before him, in Tehran's rush-hour traffic. Eyewitnesses told Iranian media that a motorcycle pulled up alongside Roshan's car and a man attached a magnetic bomb before speeding away. There was no claim of responsibility, but officials called it the work of the Zionists, Iran's term for Israel.

It was impossible to say if they were aware of remarks made Tuesday to an Israeli parliamentary by Lieutenant General Benny Gantz. Gantz predicted that 2012 would be a year in which Iran experiences increased international pressure, including, in his words, events that happen unnaturally. Nuclear analyst David Albright at the Institute for Science and International Security in Washington, speaking before the latest assassination, said Tehran must be feeling the pressure financially, diplomatically, and from covert operations.

DAVID ALBRIGHT: It knows that some of its scientists are under threat by assassination. There's been cyberattacks. There's efforts to get Iranians to defect. And we've called it kind of a third way. All those things are continuing, and that's added to the pressure.

KENYON: This is the latest in a series of increasingly belligerent signals between Tehran and Western capitals. The American and European drumbeat for ever more painful sanctions has been greeted by Iranian war games, missile tests and threats to close the vital oil shipping lanes of the Straits of Hormuz. U.S. and British warships have since raised their profiles in the Persian Gulf.

Most analysts agree that there's a built-in disincentive for Iran to try to block the Straits, the fact that it would also choke off Iran's own oil exports. But Columbia University Middle East expert Gary Sick, says there is one circumstance under which Iran might take such a drastic step: if Western sanctions against the Iranian central bank are implemented, because that would mean Iran could no longer get paid for its crude.

GARY SICK: Iran has indicated quite clearly - and I'm not sure this has been understood in the West. They've indicated that if they are no long able to sell their oil, they will regard that as a blockade or an act of war, even though it's done through the banks. In that event, they have said they're not going to just sit on their hands.

KENYON: Much of the hostility can be traced to Western fears that Iran's nuclear program includes a drive for weapons capability, which Tehran denies. Iran's announcement that uranium enrichment has begun in a hardened underground site called Fordo, near the holy city of Qom, hasn't helped matters.

Analyst Mark Fitzpatrick at the International Institute for Strategic Studies in London says the most troubling aspect of the move is Iran's current emphasis on enriching uranium to 20 percent, which is closer to weapons-grade. But he also notes that amid all the saber-rattling, Iran has offered to resume nuclear talks with six world powers. No date has been announced, and Fitzpatrick says he's pessimistic about a breakthrough anytime soon. But there may be a diplomatic component to Tehran's insistence on enriching to 20 percent.

MARK FITZPATRICK: Iran may feel that it's strengthening its hand in any upcoming negotiations by making more valuable this card of a willingness to stop producing 20 percent enriched uranium. It's probably equivalent to the Western view that by ratcheting up sanctions the West strengthens its hand, because it's a sanction that could be later withdrawn in negotiations.

KENYON: Analyst Gary Sick says a deal that sees Iran agreeing to stop its 20 percent enrichment may be the only plausible avenue for a diplomatic success in the near future. Whether that's possible in the current climate, and if it is, whether that would ease the current tensions, are among the questions now being debated in Tehran and Washington. Peter Kenyon, NPR News, Istanbul.