First paragraph of the book chapter:

How quickly could individual governments, starting from different levels of nuclear-related expertise and technology, develop a nuclear weapon if they chose to do so? This question—which I will call the “nuclear latency” question—is both exceedingly important and poorly understood. It is important because an accurate understanding of both underlying state capabilities and the time needed to utilize such capabilities is necessary to analyze a wide set of nuclear policy issues: for example, dealing with the Iran nuclear crisis (how quickly could Tehran make a weapon from its stockpile of low–enriched uranium?); understanding the relationship between the spread of civilian nuclear power and the spread of nuclear weapons capability (will new civilian programs make breakout to military programs easier and more likely?); evaluating potential NPT reforms (what would be the effects of lengthening the ninety-day notice in the Article X withdrawal clause?); or assessing the stability of a world without nuclear weapons (could disarmed states rearm in five days, five weeks, five months, or five years?). Despite widespread discussion of these policy issues, however, a set of mirror-image analytic failures has limited our ability to make clear predictions about nuclear latency and proliferation: Political scientists working on these subjects have often failed to examine basic technical factors regarding the nuclear fuel cycle that strongly influence how quickly states can get the bomb; the more technical literature about nuclear latency has similarly often failed to examine the political factors that strongly influence the ability of a government to develop nuclear weapons.

Nuclear power and nuclear weapons have a common technological foundation. In pursuit of a civilian fuel cycle-making fuel, building reactors to burn the fuel, and dealing with nuclear waste, which might include extracting some valuable by-products of spent reactor fuel-a nation can develop the capability of producing the material necessary for a bomb, either highly enriched uranium or plutonium. Under civilian cover, North Korea developed a fuel cycle ideally suited to harboring a latent capability for weapons production. In fact, although the country now has the bomb, it does not have much of a nuclear arsenal or any nuclear-generated electricity.

In the 1970s, South Korea was also interested in the bomb, but it gave up those aspirations and, with international assistance, turned its nuclear focus to civilian energy. Today the South Korean nuclear power industry provides nearly 40 percent of the country's electricity, and South Korea is in a position to become a major international exporter of nuclear power plants. The factors that led North Korea to build the bomb and those that led South Korea to forsake it can be instructive for the United States in formulating a policy to restrain Iran's nuclear weapon ambitions, although the political situation there is dramatically different.