A Romney administration probably would seek tougher penalties, which might put it at odds with a more moderate South Korean policy, although a sudden disagreement with Seoul on nuclear issues is unlikely.
North Korea, which counts China as its only major ally, has scarcely registered as an issue in the election campaign. The only Asia-related policy promise that has garnered attention has been Romney's vow to designate China as a currency manipulator, a step that could strain U.S.-China ties.
History shows that the China relationship is prone to dramatic ups and downs.
Within three months of taking office in 2001, President George W. Bush was thrust into a China crisis after a collision between a U.S. spy plane and a Chinese fighter jet.
Under Bush's predecessor, Bill Clinton, U.S.-China relations started badly, then improved, only to deteriorate sharply after the mistaken U.S. aerial bombing of Beijing's embassy in Belgrade in 1999.
EDITOR'S NOTE — Matthew Pennington covers U.S.-Asian affairs for The Associated Press in Washington.
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