Japan is not, and will not be, a major player on denuclearizing North Korea because of its intransigence on the abduction issue, according to a top U.S. expert on Japan.

Gerald Curtis, the Burgess Professor of Political Science at Columbia University, said Japan "put itself in a corner" by taking a hardline approach on the abduction issue and, as a result, it "does not have much leverage of its own" to deal with North Korea.

Aside from it being a terrible humanitarian tragedy, the abduction issue has spun out of control to become a "spur to heighten Japanese nationalism," toughening public opinion on how to deal with North Korea, Curtis said at a recent forum at The Korea Society in New York.