North Korea 's artillery barrage was serious , but this is not a crisis , say co-authors . The facility Hecker visited could only produce one or two bombs ' worth of material a year , it is not clear when it will be fully operational and it has been built to replace the plutonium production facilities , not add to them . They say the action fits pattern of North Korea 's behavior and does n't preclude progress . Comment: U.S. needs to try economic and diplomatic measures to move ahead , they say .
North Korea 's artillery barrage was serious , but this is not a crisis , say co-authors . They say the action fits pattern of North Korea 's behavior and does n't preclude progress . Comment: U.S. needs to try economic and diplomatic measures to move ahead , they say .