A better US nuclear arsenal means a safer world

As usual, Donald Trump was overstating things when he bragged on Twitter that he has made the US nuclear arsenal “far stronger and more powerful than ever before.” The US does have the world’s largest collection of its most dangerous weapons, but the work of modernizing it
predates and will outlast his presidency.
The Pentagon is in the early stages of a planned $1 trillion overhaul of the so-called nuclear triad —air-, land- and sea-based weapons—that began under President Barack Obama. It’s necessary from both a military standpoint, as much of the arsenal is so old as to be beyond repair, and a strategic one: Without a credible US nuclear deterrent, the global arms race could well intensify.
It’s not only that many aspects of the US nuclear-weapons program are outdated. It’s that threats are on the rise: Russia is renovating its Soviet-era arsenal and has deployed a ground-launched nuclear-capable cruise missile the US rightly says is in violation of a treaty. China is building nuclear-armed submarines (it already has nuclear-tipped intercontinental ballistic missiles). And North Korea has the world on edge with its missile tests.
There should be no debate about whether America’s nuclear-weapons systems need to be kept up to date. The issue will be whether Congress can push the Pentagon to be as efficient as possible. As with all defense outlays, members of Congress will undoubtedly weigh the effect of local jobs against the interests of national security.
So what is the best way to spend this trillion-dollar windfall, which will be parcelled out over the next several decades? There is justified consensus that the Navy’s planned fleet of up to 12 next-generation Columbia-class submarines, armed with improved Trident missiles, be the centerpiece of the modernization effort. The sea leg of the nuclear triad is the stealthiest and most flexible, and the accuracy of its missiles is now on a par with ICMBs.
The Air Force is moving ahead with a new long-range strike bomber, the B-21 Raider, which it says will be able to fly in contested airspace, where its aging B-1, B-2 and B-52 aircraft are increasingly vulnerable. The Air Force also wants a new nuclear-capable cruise missile that can be launched from the air outside a combat zone, which will only destabilize the nuclear balance. Many feel the same way about an improved version of the B-61 atomic bomb, which has a “dial-a-yield” feature that can make it far less powerful than the weapon dropped on Hiroshima 72 years ago this month.
There is an argument that this modernization program would make the world a more dangerous place. In terms of quality and quantity, the US is already the world’s nuclear superpower, and its efforts to upgrade could create some tension among other nuclear states. At the same time, a strong US arsenal could aid nonproliferation efforts. Without the promise of nuclear protection, US allies such as Japan and Saudi Arabia might be tempted to join the nuclear club.
At the very least, one benefit of strengthening nuclear deterrence is to gain leverage in nonproliferation negotiations. The New START Treaty, which vastly lowered caps on long-range nuclear missiles, is due for an extension in 2021. And there is the matter of Russia and North Korea’s nuclear adventurism. Diplomacy may seem an unlikely solution to these problems at the moment, but it will be far more so if the US is not negotiating from a position of strength.
Trump’s unpredictability may make diplomatic progress less likely and
nuclear conflict less unthinkable. Fortunately, US nuclear policy is far more
deliberate than his Twitter feed.
—Bloomberg