Japan's banking system can still be described as "fragile" or even "precarious" despite nearly a decade of supposed reforms and a wave of industry realignment, according to Benn Steil, New York-based senior fellow of the Council on Foreign Relations.

Speaking at the same symposium on Japan-U.S. economic relations, Steil said there is a lot more the Japanese government needs to do to clean up the financial sector.

He also questioned whether Japanese politicians really understand the meaning of reform, citing recent examples of ruling party actions that suggest government policies are not heading in the right direction.