SEOUL, South Korea (AP) -- For 20 years, fears about North Korea's headlong pursuit of nuclear bombs have been deflected by admonishments not to overestimate an impoverished dictatorship prone to bragging and tantrums.
After three nuclear tests of apparently increasing power and a long-range rocket launch that puts it a big step closer to having a missile that can carry a nuclear warhead to American shores, many believe that in a matter of years -- as little as five, maybe, though the timeframe is debated -- Pyongyang will have a very scary nuclear arsenal.
Though it's a view not embraced by everyone, one respected South Korean expert says North Korea could be working toward 80 to 100 nuclear-tipped missiles. Bruce Klingner, a former U.S. intelligence officer specializing in North Korea, provides a less dramatic but still bracing assessment: If the path is A to Z, with Z being nuclear missiles that can hit the U.S. mainland, North Korea is maybe at T.
Proof of the new seriousness with which Pyongyang's intentions are now seen can be found in the Obama administration's announcement in March that it will spend $1 billion to add 14 interceptors to the U.S.-based missile defense system. It said it was responding to what it called faster-than-anticipated North Korean progress on nuclear weapons and missiles.
"Where in the past, there may have been some ambiguity about what North Korea was seeking to achieve, there is a clear recognition that they are pressing toward a nuclear capability with a potential longer-range delivery," Kurt Campbell, the top U.S. diplomat for Asia from 2009 until earlier this year, said at a forum last week in Seoul. "Such an approach represents a strategic, almost existential threat to the United States."
The sense of urgency is new. What hasn't changed is the fierce, seemingly paralyzing debate about how to discourage North Korea's development of nuclear weapons. Some call for unconditional talks. Others say it's time for tougher, Iran-style sanctions and for China to cut off aid to its ally.
Pyongyang emerged in a new light after it put a satellite into orbit on the tip of a long-range rocket in December -- beating much richer Seoul to that goal. Then in February, it conducted a nuclear test that, while details remain unclear, appeared to be its most powerful yet. It followed those moves with a torrent of threats in March and April in response to U.N. sanctions and huge U.S.-South Korean military drills.
"It's quite understandable that people are spooked. The only mystery is why it's taken so long," Jeffrey Lewis, a nonproliferation specialist at the Monterey Institute of International Studies, wrote in a blog post in mid-April.
Analysts now put the North's arsenal at four to eight plutonium bombs. They also suspect it is making fuel for uranium bombs, but they don't know how much.
The suspected bombs aren't thought to be small enough to put on long-range missiles, but some analysts believe Pyongyang may be able to arm shorter-range missiles with warheads.
Pyongyang's weapons probably aren't meant to carry out nuclear threats, analysts say, but instead to protect against perceived outside hostility while extracting diplomatic and aid concessions. Pyongyang insists that it needs nuclear weapons to defend against a U.S. attack. Washington insists it has no such intention.
Here's how one prominent analyst sees the future of Pyongyang's atomic arsenal. North Korea's leaders have been closely studying their nuclear history, and Pakistan, which helped Pyongyang's nascent nuclear program and which built its own atomic arsenal outside international treaties, is probably an inspiration, said Hahm Chaibong, president of the conservative Asan Institute in Seoul.
With that model in mind, the goal then could be a "minimum operational nuclear capability" of 80 to 100 nuclear missiles, including some that could reach the United States, Hahm estimated. The weapons would be hidden around the country to prevent detection, in caves, tunnels, amid conventional missile stockpiles, in dense population centers and on mobile launchers, Hahm said in an interview. He speculated that such an effort could take five to 10 years.
One hundred warheads in five years is probably alarmist, Matthew Kroenig, a nuclear expert at Georgetown University, wrote in an email, but "it would be naive to assume that Pyongyang will keep a small and primitive arsenal forever. Rather, it is likely that they will rapidly move to expand their arsenal and means of delivery."
Many analysts believe it has taken so long to come to terms with North Korea's intentions because of a long history of chronic underestimation.