Newly elected British Labour leader Jeremy Corbyn upset the deterrence apple cart when he revealed that he wouldn’t launch nuclear weapons should he become prime minister. Chief of Defence Staff Sir Nick Houghton protested; at Huffington Post UK, Paul Waugh quoted Corbyn’s response:
“It is a matter of serious concern that the chief of the defence staff has today intervened directly in issues of political dispute. It is essential in a democracy that the military remains political neutral at all times.”
But Houghton said “the reason I say this, and it is not based on a personal thing at all, it is purely based on the credibility of deterrence.”
“The whole thing about deterrence rests on the credibility of its use.”
In other words, if a state has nuclear weapons and it’s the victim of a nuclear attack (or first strike), it feels bound to fulfill the deterrence contract and retaliate (a second strike). Otherwise, the state’s threats will never be taken seriously again.
The fallacy in that argument is that what hurts the credibility of deterrence even more is that, if nuclear war breaks out, it means that nuclear deterrence has failed. Not only that, once the world gets a load of the results of a nuclear war, nuclear programs as a whole will have lost their credibility. In other words, it doesn’t matter if the credibility of deterrence is undermined because it will likely never be used as a policy again.
Another troublesome aspect of deterrence is highlighted in an article on the precarious nature of the nuclear taboo in the new Bulletin of the Atomic Scientists by James Doyle:
Potentially lethal tension exists between nuclear deterrence and the nuclear taboo because the effectiveness of a nation’s nuclear deterrent depends on the credibility of its threat to use those weapons. If one state believes its rival will refrain from nuclear retaliation due to a desire to preserve the nuclear taboo, that state may be less deterred to initiate a nuclear attack.
“Nuclear-armed states could take steps to strengthen and formalize the nuclear taboo,” Doyle continues, “but they have not done so.”
They could all adopt a declaratory policy stating that nuclear weapons will only be used as a last resort and agree never to use them first in a conflict. … States could also configure their nuclear forces so they could not be used promptly in a crisis or to launch a disarming first strike against a potential adversary’s nuclear forces. States have failed to take these steps because they fear it will weaken deterrence. The nuclear taboo thus remains a fragile firebreak against nuclear catastrophe.
In other words, nuclear deterrence is just one big house of cards.