Correction: An earlier version of this column incorrectly stated the Bulletin of the Atomic Scientists adjusted its “doomsday clock” in June. The clock was changed last January.

The new leader of the British Labour Party, Jeremy Corbyn, has sparked a political firestorm by challenging the myths around nuclear weapons and Cold War deterrence. Corbyn announced that he would never use a nuclear weapon. He followed that apostasy by declaring that he opposed renewal of the British nuclear Trident submarine program.“I am opposed to the use of nuclear weapons. I am opposed to the holding of nuclear weapons. I want to see a nuclear-free world. I believe it is possible,” Corbyn declared.

Several Labour shadow ministers suggested they might resign if that became Labour’s policy. Conservative Prime Minister David Cameron and the right-wing British press have been pillorying Corbyn as a threat to national security for his heresy.

Corbyn’s aides argue this is not a new version of the debate over unilateral disarmament that wracked Labour in the 1980s. Rather, they insist the question is whether renewing the fleet is worth the money. Corbyn’s doubts are shared by some current and retired military officers. The British fleet of four Trident submarines is slated for retirement in the late 2020s. It will take almost that long to develop a successor. Renewing and operating the Trident program will cost an estimated 167 billion British pounds over the next four decades. The Army has already been reduced to below 82,000 soldiers, the lowest number since the 1700s. Renewing the Trident fleet would likely force more cuts.

Corbyn says the Trident isn’t worth the money. It is a costly weapon that can never be used. British security concerns should be focused on terrorism, economic turmoil and catastrophic climate change; nuclear weapons are irrelevant to all that. Corbyn argues, sensibly, that the Cold War era is long gone. “There are five declared nuclear weapon states in the world. There are three others that have nuclear weapons. That is eight countries out of 192,” he told reporters. “187 countries don’t feel the need to have a nuclear weapon to protect their security, why should those five need it themselves?”

British forces — particularly special forces — are active in countering terrorists. British intelligence is valued highly. But British nuclear weapons are at best extraneous, and at worst a dangerous, unusable threat. Budget choices have to be made.

The Corbynites are sensitive about being accused of unilateral disarmament, since the party’s adoption of that position in the 1980s at the height of Cold War tensions was electorally damaging. Yet a British commitment to give up nuclear weapons unilaterally might just be the highest and best use of the Trident fleet.

The Nuclear Non-Proliferation Treaty (NPT) entered into force in 1970; 190 countries have subscribed to it. At its core, as the State Department notes, is a “basic bargain”: “Countries with nuclear weapons will move towards disarmament; countries without nuclear weapons will not acquire them; and all countries can access peaceful nuclear technology” (emphasis added). With the end of the Cold War, Russia and the United States reduced their arsenals dramatically. They also cooperated, as the Soviet Union split apart, on consolidating control over nuclear materials and scientists. Ukraine, Kazakhstan and Belarus all gave up the arsenals they had inherited when the Soviet Union broke up. South Africa renounced the bomb. Libya agreed to give up its weapons of mass destruction.

In recent years, however, as tensions have built up between Russia and the United States, the momentum in adhering to the NPT has been lost. In 2002, President George W. Bush pulled the United States out of the Anti-Ballistic Missile (ABM) treaty. Both countries have announced costly programs to modernize their nuclear triads (i.e., land, air and sea weapons), undermining existing treaties. The Obama administration has remained committed to deploying an anti-missile system in Eastern Europe.

Worse, both countries still deploy hundreds of nuclear warheads on hair-trigger alert. Both have embraced unstable “launch on warning” policies that call for a split-second decision to launch before getting hit. And now tensions are mounting, with air and naval incidents spiking. Turkey’s recent decision to shoot down a Russian plane that allegedly briefly flew over its airspace is illustrative.

Last January, the Bulletin of the Atomic Scientists moved its “doomsday clock” to three minutes to midnight, the first such adjustment in three years. The scientists declared that “unchecked climate change, global nuclear weapons modernizations, and outsized nuclear weapons arsenals pose extraordinary and undeniable threats to the continued existence of humanity.” Former U.S. defense secretary William Perry now warns that the “probability of a nuclear calamity is higher today . . . than it was during the Cold War.”

In recent months, the United States and Russia have worked together to achieve the historic Iran disarmament agreement, with the Islamic republic agreeing to forgo development of nuclear weapons and to an extensive inspection regime to police it. This is a moment to push progress on nuclear disarmament. The United States should move to revive the anti-ballistic-missile treaty protocols, and to draw down its nuclear arsenals. We should renounce first use and join with the Russians in moving our weapons off of hair-trigger alert. A unilateral declaration of nuclear disarmament by Britain would add measurably to this progress. It would enable Britain to join with others in building international pressure on the countries with nuclear weapons , from the United States and Russia to North Korea, India and Pakistan.

Corbyn is now taking a beating in the conservative tabloids for his blasphemies. Yet he is talking common sense. No leader in his right mind would use nuclear weapons. The British people would be better off spending the money that renewal would cost elsewhere. The reality is that the British nuclear arsenal will have greater global significance if it is dismantled rather than renewed. Corbyn is meeting fierce resistance, even inside his own party, but he is raising questions that deserve a full debate.

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