If North Korean leader Kim Jong Un is truly committed to the "complete denuclearization" of the Korean Peninsula, then there is much to look forward to as Kim begins a series of summits with South Korean President Moon Jae-in and U.S. President Donald Trump. Skepticism is in order, however. It is not clear if Kim's definition of denuclearization matches that of the rest of the world, nor can we be certain that he will honor promises made in those meetings. Jaw-jaw is always preferable to war-war, but diplomacy can only succeed if it is realistic and hard-nosed.

We have come a long way in nine months. In August, Trump was dismissing Kim as "little rocket man," and warning that a miscalculation would prompt "a fire and fury like the world had never seen." Kim responded by calling Trump "a mentally deranged U.S. dotard." Yet since the beginning of the year, Kim has engaged in a diplomatic charm offensive that produced North Korean participation in the Pyeongchang Winter Olympics, a meeting with Chinese President Xi Jinping, a summit this week with Moon and a scheduled first meeting between a sitting president of the United States and his North Korean counterpart.

To show his good faith, Kim has promised to suspend nuclear and missile tests, to close his country's nuclear test site, and according to South Korean sources, he is no longer demanding the removal of U.S. forces from South Korea as a condition of denuclearization. Chief Cabinet Secretary Yoshihide Suga has called this "a step forward and we welcome it as a positive move." While he is right, there is less to those promises than meets the eye.