On July 24th, former London mayor Boris Johnson became the newest Prime Minister of the United Kingdom. According to tradition, one of the first actions taken by each new PM, following a briefing regarding the state of Britain’s nuclear capabilities, is to write and seal identical letters to the commanding officers of four British nuclear submarines. Called the ‘Letters of Last Resort,’ they contain instructions for what should happen in the event that UK leadership is incapacitated and unable to issue final orders. Because each UK leader writes their own letters, which are then locked inside a safe-within-a-safe on board each submarine and are destroyed without being opened when a new PM takes office, these letters will only be read in a worst-case scenario of apocalyptic proportions. To date, the specific contents of any such letters remain unknown to all but their authors.
Nevertheless, conventional wisdom indicates that there are four broad possible options for these final directives:
- Fire upon particular targets (including, but not limited to, those guilty of attacking the UK).
- Do not fire.
- Use your own judgment regarding what to do.
- Surrender the submarine (and its payload) to a particular ally.
With one exception, no former prime minister has ever spoken out regarding their thinking on which option was best: James Callaghan (who held the office from 1976 to 1979) indicated his general support for (1) – though only reluctantly as an absolute last resort which, if he were still alive to witness, he would regret until he died. While neither Johnson nor his Conservative predecessor Theresa May have commented publicly on their opinions, Labour party opposition leader Jeremy Corbyn has long been an outspoken proponent of nuclear disarmament, suggesting that he might support (2).
For some, a defense mechanism like this is a sensible element of a wider approach to global relationships between nuclear powers. The logic of a foreign policy founded on ‘mutually assured destruction’ (MAD) requires a nation’s enemies to understand the retaliatory capability of that nation, should it be attacked first. Birthed particularly as a result of the Cold War (where the standoff between the USA and the USSR was famously complex), MAD doctrines have only become more complicated as the list of countries with nuclear capabilities has grown over the last six decades. In short, on this perspective, even if they are never read, knowledge that the Letters of Last Resort exist serves as a reminder to potential enemies of the UK that, should London fall, London’s attackers will fall as well – the letters are, effectively, a nuclear-level deadman’s switch.
For others, the letters are an antiquated method of problem-solving which fails to account for any number of important variables which, in the event of a disastrous attack, would surely be relevant facts to consider. How hard might it be, for example, for a team of clever con artists to fake enough of a situation that one of the submarine commanders could be convinced to open the safeguarded letter? Or, in the event of a real emergency, what happens if the letter indicates that a submarine should fire upon a target disconnected from the actual threat? Or if they specify a target that had already been destroyed? Enshrining a particular set of instructions that are (in all likelihood) impenetrable to being updated by new information is a curiously rigid system for handling any sort of governmental program – particularly one with such dire potential consequences as a nuclear missile.
Additionally, as Ron Rosenbaum, author of How the End Begins: The Road to a Nuclear World War III, explained in an article for Slate, notifying the world that the Letters of Last Resort only might require retaliation undercuts the entire foundation for MAD in the first place; as Rosenbaum puts it, “With all due respect to our British cousins, this seems, well, insane.”
Other countries with nuclear technology have developed more complicated security measures, technological firewalls, communication networks, and backup plans to serve as alternatives in the event that one or two systems fail. The US, for example, has turned the country’s nuclear power into a badge of authority, sending the so-called ‘Nuclear Football’ and its attendant along wherever the President of the United States happens to go (a system mimicked by Pakistan, Russia, and possibly France). But these systems suffer from limitations of their own. In January of 1995, for example, a scientific rocket designed to study the Northern Lights was launched from Norway; confusion in nearby Moscow led to the Russian Football (called the cheget) being temporarily activated, though ultimately no attack was issued – perhaps the closest the world has come to the brink of nuclear disaster since the infamous Petrov incident of 1983.
It remains to be seen what a Boris Johnson administration will mean for Britain and the rest of the United Kingdom, but – by now – the Johnson Letters of Last Resort have been penned and secured beneath the waves. Until, and unless, a more secure system for managing such destructive weapons can be devised, we must continue to hope that those letters remain unread.