The second round of negotiations to create a global treaty to outlaw nuclear weapons started last week at the United Nations and is scheduled to conclude July 7. Japan, which relies on the U.S. nuclear umbrella, has boycotted the talks, apparently out of concern that its participation could complicate its relationship with the United States. The Abe administration should reconsider whether its stance is beneficial for Japan — the only nation in history to suffer a nuclear attack. Japan should take part in the negotiations and seriously seek ways to bridge the differences between the nuclear weapons powers, which oppose the treaty, and the non-nuclear weapons states that are pushing forward with the accord. A failure to take concrete action in this direction could imperil Japan's credibility as a country serious about nuclear disarmament.

Last December, the U.N. General Assembly adopted a resolution calling for the start of the treaty talks, with 113 members voting for it and 35 others, including the U.S., Russia, Britain and France — all of which are nuclear powers — and Japan, voting against it. Thirteen other members, including China and the Netherlands — a NATO member that is under the U.S. nuclear umbrella — abstained from the vote. Following the first round of negotiations on the prospective treaty, Costa Rica, which serves as chair of the talks, submitted a draft treaty in late May.

It is significant that the planned treaty's basic ideal is founded on "the catastrophic humanitarian consequences that would result from any use of nuclear weapons," a phrase appearing at the outset of the preamble, and that it takes into consideration the pains of survivors of the nuclear-bombed cities of Hiroshima and Nagasaki, who still suffer from health damage caused by the radiation and have played an important role in rousing global opinion against nuclear arms. The preamble says the catastrophic consequences of nuclear weapons "pose grave implication for human survival" and mentions "the suffering of the victims of the use of nuclear weapons (Hibakusha) as well as of those affected by the testing of nuclear weapons."