February 6, 2020

The United States Department of Defense on February 4 made public that the low-yield new variant of nuclear warhead, W76-2, has been mounted on submarine-launched ballistic missile(s) (SLBM). According to the Federation of American Scientists, this type of warheads was already deployed aboard the Ohio-class strategic submarine Tennessee which left for the Atlantic at the end of last year and is now on duty there.

This move goes counter to the ongoing global effort to achieve a world free of nuclear weapons with the adoption of the UN nuclear weapons ban treaty, and will have a serious impact on Japan’s security environment. It is necessary to keep a watchful eye on U.S. moves.

The deployment of the new nuclear warhead is carried out in line with the Trump administration’s Nuclear Posture Review (NPR) released in February 2018.

The main pillar of the 2018 NPR is to add lower yield “usable” variants of nuclear warheads to the U.S. arsenal. Currently, the U.S. has 14 nuclear submarines capable of being equipped with nuclear weapons (SSBN), and eight of them are in the Pacific, but no SSBN has ever visited Japan. Given that the NPR has China and Russia as potential enemies in mind, the latest DoD announcement about the nuclear warhead deployment could fuel nuclear arms races in North East Asia.

In addition, the Pentagon already started working on a project to update F-35 stealth fighters so that they can be armed with the new nuclear warhead B61-12.

Furthermore, having pulled out from the Intermediate-Range Nuclear Forces Treaty with Russia, the Trump administration is considering deploying mid-range ballistic missiles anew among its Asian allies, including Japan. This explains why the U.S. is urging Japan to set up the ground-based missile defense system Aegis Ashore on its territory. If the Japanese government keeps depending on U.S. nuclear deterrence, Japan will be again taken advantage of by the U.S. to pursue the U.S. nuclear strategy.

Past related articles:
> New US NPR will enhance likelihood of bringing-in nukes into Japan: JCP Fujino [February 15, 2018]
> Hibakusha condemn Trump’s new nuclear weapons strategy [February 4, 2018]