Disclosure of North Korea's role in building a Syrian nuclear plant suggest a White House bid to bring Pyongyang to account for spreading arms technology to the Middle East.
The announcement in Washington came right after US diplomats held talks in Pyongyang in which they had hoped to persuade North Korea to initial a compromise acknowledging concerns about its deal with Syria and its programme for enriching uranium.
As a reward for that much co-operation, the US would drop North Korea from the State Department's list of terrorist countries and lift economic sanctions.
US reluctance to attack North Korea's nuclear facilities after years of efforts to get the North to abandon the programme contrasts with the Israeli response last September to the threat posed by the Syrian facilities.
Although the US has repeatedly assured North Korea that it has no intention of staging a 'pre-emptive strike', Israel set a precedent that US strategists may not want to overlook.
The fact that the White House, rather than the State Department, outlined the nuclear connection between Syria and North Korea indicates a rift between officials on confronting North Korea.
One great question is whether President George W. Bush and South Korean President Lee Myung-bak agreed on the need for disclosure of the Syrian programme when they met recently in the US.
Mr Lee has upset North Korea since his inauguration by adopting a tough 'pragmatic' policy that contrasts with the 'sunshine policy' initiated by Kim Dae-jung. Mr Kim's successor, Roh Moo-hyun, upset the US administration by advancing on that policy, lavishing food and fertiliser on the North while demanding very little in return.
Mr Lee has called for 'reciprocity' for whatever is done to help North Korea, which is suffering from severe food shortages. He also demands 'verification' of any deal with the North. He made it plain to Mr Bush that he was not excited about any compromise, warning against a 'temporary achievement' that would do little in the long run.
One reason for Mr Lee's happiness about the courtesies extended by Mr Bush at Camp David was, presumably, an understanding for the White House to publicise the Syrian programme in a final bid for North Korean acknowledgement.
Mr Kim, in a talk at Harvard's Kennedy school, predicted that Mr Lee would soften his stand on North Korea. He saw a parallel between Mr Lee's strongly worded remarks and the hawkish outlook of Mr Bush during his first term as president.
'After six years, President Bush realised this was not working,' Mr Kim said, and entered negotiations with North Korea 'since the US cannot wage another war'.
But the timing of the White House briefing on the Syrian programme raises the stakes. Face-saving compromises, as Mr Lee intimated, will not work. More tough talk will be needed if North Korea is to get out of the nuclear business.
Donald Kirk is the author of two books and numerous articles on Korea for newspapers, magazines and journals