North Korea's acts as baffling as ever

This is the title of an article by John McBeth in the ST today to describe the sinking of Cheonan. He could not find a sensible reason for the North Koreans to do such an act. And as national leaders, one must assume that they are thinking people and will act only when they are to benefit from it. There must be good reasons for them to sink the South Korean ship. But apparently there were none.