Antinuclear

In recent years, the Pentagon has increased the overall offensive power of its nuclear arsenal. Those changes, along with further upgrading, will amount to more destructive power from all three legs of the American nuclear triad: sea, land and air-launched nuclear weapons.

From the sea, a nuclear missile “super fuze” timing element improves the accuracy of submarine-based warheads by allowing for detonation closer to targets. The United States began incorporating this new fuze system into the ballistic-missile submarine fleet in 2009, and some analysts believe the entire submarine force has already been equipped with the technology.

And last week, the Pentagon announced that it had awarded contracts for updated versions of both the ground-based nuclear intercontinental ballistic missile arsenal and the air-launched nuclear-tipped stealth cruise missile, designed to penetrate enemy territory undetected.

According to some nuclear weapons experts, enhancements like the super fuze have increased by up to threefold the destructive capacity of America’s nuclear arsenal. And Andrew C. Weber, a former assistant defense secretary, recently described the upgraded stealth cruise missiles as “a destabilizing system designed for nuclear war fighting,” rather than a necessary addition to the system of nuclear deterrence.

When initially planned during the Obama administration, the upgrades were paired with commitments to nuclear-arms reduction and a policy that narrowed the conditions under which the United States would use its nuclear weapons. The upgrades will continue under President Trump, but there is no sign that they will be accompanied by the kind of limitations on their use advocated by his predecessor.

Washington’s defensive capacity is centered on the deployment of batteries of missile interceptors — most notably the Terminal High Altitude Area Defense and the Aegis systems — and space-based technology to track incoming missiles in real time.

This missile shield is still in the early stages of development and has a mixed record of defending against missile attacks. It is incapable of stopping a full-scale missile barrage and is a long way off from attaining that ability.

But America’s commitment to missile defense, even to systems that have yet to work well, coupled with an aggressive improvement of offensive capacity, is worrisome to other nuclear-armed states, particularly Russia and China.

Both countries have already been working on building more modern nuclear weapons systems. Moscow is playing catch-up with the far superior United States forces, modernizing all three arms of its own nuclear triad. Beijing is upgrading and expanding its own ICBM-equipped nuclear submarine fleet, and seeking to ensure its access to strategic waters.

But we can count on Russia and China to accelerate their nuclear programs in the face of America’s strategy. Former Defense Secretary William J. Perry has argued that the enhanced stealth cruise missile will pressure Russia and China to bolster their systems. And President Vladimir Putin of Russia has cited America’s development of a missile shield as reason to build up his nation’s nuclear strike power.

We should indeed worry about the Kim regime’s nuclear weapons program and its cavalier references to nuclear war. But we should also be concerned by Washington’s expansion of a nuclear war machine under a commander in chief who has publicly questioned longstanding American nuclear policy.

One difference between Mr. Kim and Mr. Trump is that when the United States president threatens to unleash “fire and fury like the world has never seen,” he is actually able to do so.  Stuart Rollo is a writer and researcher at the Sydney Democracy Network at the University of Sydney.