The US House of Representatives followed by the US Senate recently passed an expenditure bill containing a reference to House of Representatives Resolution 121 (or H.Res 121), which President Barack Obama subsequently signed into law. Put simply, H.Res 121 urges the Japanese government to address the issue of "comfort women" - more than 20,000 women of Korean, Chinese and other nationalities who were forced into sex slavery by the Japanese imperial forces before and during World War II.

More specifically, H.Res 121 urges the Japanese government to "formally acknowledge, apologize and accept historical responsibility in a clear and unequivocal manner" for this wartime atrocity. It also exhorts Japanese Prime Minister Shinzo Abe to "apologize in a public statement", and the Japanese leadership "to refute claims denying the existence and purpose of the system as well as to educate current and future generations about this horrible wartime crime".

This means US Congress is asking the US leadership, particularly the US State Department, to apply diplomatic pressure on Japan to address this and other historical issues more constructively. Although H.Res 121 is a non-binding document attached to the Consolidated Appropriations Act for the 2014 fiscal year, it is the first such to be included in a US Congress bill.