Trump’s unpredictable nuclear policy These bombs are not weapons: they’re instruments of diplomacy

The most important phrase in Walter’s statement is “limited diagnostics”. That’s effectively an admission that the rationale is politics, not technology. In an event hosted by the Mitchell Institute on 26 May, Walter revealed that the time necessary to prepare for “a fully diagnostic” test that provides “lots of data, all the bells and whistles … might be measured in years”. The US, however, is in a hurry.

Nuclear tests are almost always motivated by political purposes. Physicists know their stuff; they have a good idea whether a device will work and what the yield will be. The very first device exploded over Hiroshima in 1945 was, for instance, not actually tested beforehand because Manhattan Project scientists knew it would work. The second bomb, exploded over Nagasaki, was tested a few weeks earlier at Alamogordo, New Mexico, only because it involved more complicated implosion technology.

That Alamogordo test was arguably the only one in history free of propaganda motive. Every subsequent one has carried with it an element of sabre rattling. During the Cold War, tests became a method of waging war by other means, a way of saying: ‘Beware’. When the US conducted a series of tests in July 1946 at Bikini Atoll, they invited 170 journalists from around the world. A floating press office made sure the news got out.

In 1961, the Soviets exploded the largest ever device, a 57 megaton bomb, over Novaya Zemlya in the Arctic. Nicknamed Tsar Bomba, it was far too large to be used in war, since it could not be carried by plane or missile. Its sole purpose was to intimidate. Nowadays, when Kim Jong Un explodes a bomb, he knows beforehand that it will work; his purpose is merely to unnerve the United States. Nuclear testing is, and has always been, a pissing contest.

Computer modelling enables atomic engineers to calculate whether a device will work and what its yield will be. Since 1945, modelling has become more sophisticated and reliable. Granted, mistakes have occasionally been made. For instance, when the US exploded its first hydrogen bomb in November 1952, the yield exceeded the most optimistic predictions. When physicists ran their equations again, they realised they’d overlooked a crucial element in the chain reaction that produced extra neutrons leading to a greater yield.

Errors like that, however, are immaterial to nuclear politics. These bombs are not, in truth, weapons: they’re instruments of diplomacy — devices designed to ensure security through deterrence. Their importance lies in their existence, not in their use. If they’re used, that means they’ve failed in their sole purpose to prevent nuclear war.

But paranoia is always appropriate when the issue is nuclear annihilation. In 1962, the US was deterred from nuclear war by a handful of medium range Soviet missiles in Cuba. At the time, the US arsenal was perhaps 14 times larger than the Soviet Union’s, but, as Defense Secretary Robert McNamara later admitted, it wasn’t worth losing Chicago in order to destroy the USSR. Likewise, since 1962, China has achieved deterrence with a relatively small arsenal compared to other nuclear powers.

Tests upset this fragile balance. Deterrence depends upon the predictability of nuclear nations and their leaders; tests inject a worrying element of uncertainty. We’ve seen that with Kim and, earlier, with the secrecy surrounding Saddam Hussein’s nuclear intentions. It’s important to reiterate a simple point: nuclear tests are always political.

The fear aroused by the Cuban Missile Crisis led John Kennedy and Nikita Khrushchev to negotiate the Partial Test Ban Treaty (PTBT) in August 1963. It prohibited tests in the atmosphere, on the seabed and in outer space. The treaty did not end testing; in fact, the frequency actually increased, but all tests were conducted underground. That agreement is nevertheless immensely important as a symbolic gesture. The nuclear adversaries had agreed on a common purpose. In my view, the PTBT was more important to international harmony than any of the later SALT or START agreements, which did little to limit nuclear proliferation.

The same could be said of the Comprehensive Test Ban Treaty (CTBT) of 1996, adhered to by 184 nations. The US has not formally ratified the treaty (the Senate rejected it in 1999), but it has followed the spirit of the agreement by not testing.  The CTBT is important because it set a standard of behaviour accepted by almost all countries on Earth. That in turn makes possible the censure of rogue nations like Iran and North Korea.

In his 2018 Nuclear Posture Review, Trump indicated that he would not seek ratification of the CTBT.  He also recently indicated that he wants to rescind the Treaty on Open Skies, a 2002 agreement designed to reduce the chances of accidental war by allowing mutual reconnaissance flights. These actions, when combined with recent talk of resuming testing, have suddenly made the world a more dangerous place. The US is now unpredictable and predictability is essential to nuclear harmony.

An American test will be like firing a starter’s pistol in a new arms race. “It would be an invitation for other nuclear-armed countries to follow suit”, argues Daryl Kimball, executive director of the Arms Control Association. “You would also disrupt the negotiations with North Korean leader Kim Jong Un, who may no longer feel compelled to honor his moratorium on nuclear testing.’”

It’s possible that rumblings about testing are just a diversion designed to distract attention from Trump’s failures on the Covid-19 front. But I don’t think so. I think this was always on the cards. Trump has already indicated that he holds no respect for the age-old rules of international diplomacy — he thinks he knows a better way to run the world. And that’s frightening. Deterrence has always depended on international leaders understanding the intricacies of nuclear diplomacy and the simple fact that these weapons should never be used. It has worked because leaders were always rational: they could be trusted to stop short of nuclear annihilation.

Donald Trump is not a rational man. He has already shown that he does not understand nuclear diplomacy. A resumption of testing would be the biggest mistake of his already chaotic presidency.