As talks began last week at the United Nations on a treaty that would outlaw nuclear weapons, Japan announced that it will not take part in the negotiations — which is most regrettable. The move could be taken as an indication that Japan is giving up its moral responsibility as the world's sole victim of nuclear attacks to play a proactive role in global efforts to eliminate nuclear weapons, and it will come as a great disappointment to people, including survivors of the 1945 atomic bombings of Hiroshima and Nagasaki, and non-nuclear states. At the very least the government needs to explain in concrete terms how it otherwise intends to work toward its stated goal of making the world free of nuclear arms.

Austria, Brazil, Ireland, Mexico, South Africa and Sweden took the initiative in submitting to the U.N. a resolution calling for starting talks on such a treaty. Despite opposition from the United States and other nuclear weapon powers, the U.N. General Assembly in December adopted the resolution with 113 member states voting for it, 35 countries voting against and 13 others, including China, abstaining from voting. Proponents of the talks on such a treaty cited the International Court of Justice's 1996 advisory opinion that "the threat or use of nuclear weapons would generally be contrary to the rules of international law applicable in armed conflict, and in particular the principles and rules of humanitarian law." The first round of the talks took place last week and the second round is set to be held from mid-June to early July.

In addition to the nations possessing nuclear arms — the U.S., Russia, Britain, France, China, India, Pakistan, Israel and North Korea, Japan and most members of NATO also oppose the negotiations on the treaty because they are under the U.S. nuclear umbrella. The U.S. administration of President Donald Trump is reported to have expressed strong opposition to its allies participating in the U.N. talks.