On the radar: Threats subside, chance of provocation or negotiation; Nuclear guidance study still unfinished; Ban Ki-moon visits Pentagon; Diminishing role for nuclear weapons; Ratcheting down resolution’s rhetoric; and Seismic risk and Iran’s nuclear program.

April 18, 2013 | Edited by Benjamin Loehrke and Alyssa Demus

De-escalation - Government officials and experts increasingly assess that North Korea is easing off its threats and bluster, “showing signs that it wants to reduce tensions with South Korea and the United States,” reports Chico Harlan of The Washington Post.

--“The tensions should gradually decrease from here, but we cannot [be complacent]...We do still have to be prepared for any provocations,” said one South Korean Defense Ministry official.

--“If North Korean leader Kim Jong Un is indeed ready to de-escalate, the strategy would fit a pattern established by his father, Kim Jong Il, who occasionally raised the threat of war as a way to win concessions from the West and from South Korea. The pre-talks concessions the North asked for Thursday appear far-fetched, but could mark the starting line for negotiations, some North Korea watchers say,” reports Harlan. http://wapo.st/Z0wv2Q [1]

DPRK’s demands - After rebuffing initial offers for dialogue, North Korea announced its preconditions for resuming talks on Thursday. “Before talks can resume...the U.S. must withdraw all nuclear weapons assets from South Korea and the region.” South Korea must also cease all negative rhetoric directed at the North.

--In response to the North’s demands, South Korea’s Foreign Ministry said it “strongly urges North Korea to stop this kind of insistence that we cannot totally understand and go down a path of a wise choice,” reports the Associated Press. Full story here. http://owl.li/kbHQl [2]

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Nuclear procrastination review - After a year or two of work, the Obama administration has not finished its review of US nuclear deterrence requirements and operational plans. ”The analysis is not yet complete, but our preliminary view based on work to date, is that further reductions consistent with the national security environment will be possible and that continuing modernization of our nuclear capabilities is essential,” said Madelyn Creedon, Assistant Secretary of Defense for Global Strategic Affairs in a SASC hearing yesterday. Written testimony here. (pdf) http://1.usa.gov/12pFpGT [7]

Tweet - @BenFreemanDC [8]: "Missile defense is apparently so urgent the Pentagon doesn’t have the time to build it right." http://bit.ly/11hbmQo [9]

Longread - “Military Power in World Politics in the 21st Century” by Alexei Arbatov in Russia in Global Affairs.

--Abstract: “The role of nuclear deterrence in the great powers’ efforts to ensure their security will continue to decline, despite Russia’s current attempts to assign a more significant role to it and notwithstanding the present deadlock in nuclear disarmament.” http://bit.ly/175CTql [10]

Ban visits Pentagon - “Ban Ki-moon will become the first sitting United Nations secretary general to visit the Pentagon when he meets with Defense Secretary Chuck Hagel and Joint Chiefs Chairman Martin Dempsey on Thursday to discuss the North Korean crisis,” reports Kevin Baron at The E-Ring. http://atfp.co/175GYuE [11]

Tweet - @BrookingsInst [12]: Does North Korea have a reliable nuclear-armed ballistic missile? Not likely, says Steven Pifer. ow.ly/kaJU7 [13]

Rebalancing - “A panel of former senior American officials and outside experts, including several who recently left the Obama Administration, issued a surprisingly critical assessment of American diplomacy toward Iran on Wednesday, urging President Obama to become far more engaged and to reconsider the likelihood that harsh sanctions will drive Tehran to concessions,” reports David Sanger of The New York Times. http://nyti.ms/ZugDnS [14]

--Sanger reviews the recommendations of the new report from the Iran Project, “Strategic Options for Iran: Balancing Pressure with Diplomacy.” Available here (PDF via scribd). http://bit.ly/ZzYGkD [15]

Senate softens resolution - A modified version of the joint resolution that “pledged unconditional U.S. support for an Israeli strike on Iran” will move on to be considered by the full Senate. Key changes that tempered the resolution’s language include - clarifying “that the U.S. will judge what is and is not genuinely an act of self-defense,” narrowing the definition of self defense to actions against “Iran’s nuclear weapons program” instead of all Iranian targets; and clarifying that “support for Israel in such a case must be in accordance with U.S. law,” writes Ali Gharib in The Daily Beast. Full story here. http://owl.li/kbMdS [16]

Supercomputer - The Sequoia supercomputer at Lawrence Livermore National Laboratory - one of the most powerful computers on the planet - is going to be shifted over to focus on simulating nuclear blast calculations, part of the labs’ efforts to strengthen confidence in nuclear weapons behavior. Aliya Sternstein of NextGov has the story. http://bit.ly/11h6T0i [17]

On shaky ground - Recent earthquakes in Iran “have raised global concerns” over the safety of Iran’s nuclear plants. Iran’s nuclear facilities are built to withstand a quake of up to 6-6.7 on the Richter scale. Tuesday’s quake registered at 7.8. That said, experts stress that the recent earthquakes in Iran should not be overstated. While alarming, “its not comparable to the 9-magnitude quake that hit Fukushima,” writes Jillian Keenan at The Atlantic. Full story here. http://owl.li/kbVN9 [18]

Backgrounder - “Iran’s Nuclear History from the 1950s to 2005” by the Institute for Science and International Security. (pdf) http://bit.ly/ZBQ8IZ [19]

Events:

- “Nukes, Missiles and Feints: The Real Deal on Iran and North Korea,” discussion with L. Gordon Flake, Laicie Heeley, Alexandra Toma, Rachel Kleinfeld. April 19, 9:30-10:45 a.m. @ Center for National Policy. Details here. http://owl.li/kbAA8 [20]

--Senate Armed Services Subcommittee on Emerging Threats and Capabilities, hearing on Proliferation Prevention Programs. Madelyn Creedon, Kenneth Myers, and Anne Harrington. April 23, 2:30 p.m. @ 222 Russell Senate Office Building. Webcast here. http://owl.li/kbQOG [21]