Nuclear disarmament is once again addling Britain’s Labour Party. Unfortunately, the debate is riddled with the all-too-common and internalized falsehood that nuclear arms are in themselves immoral and that the world would be better off without them.

Long an objective of the party’s new leader, Jeremy Corbyn, the proposal to unilaterally disarm has spurred resignation threats, divided the leadership and affiliated trade unions, and — more than any other issue — defined Corbyn’s shadow cabinet reshuffle earlier this month.

“Moralists” and “pragmatists” argue the respective merits of leading by example — disarming in accordance with the Nonproliferation Treaty — and taking a more measured approach, advocating disarmament and nonproliferation while maintaining a minimum deterrent.

The pragmatists are in the majority and they are, in turn, supported by the majority of voters. They begrudgingly accept that wielding such ghastly weapons is necessary in a still-dangerous world. This argument has carried the day in Britain since 1952, but it routinely surrenders the moral high ground to “ideal world” happy-talk.

Writing for The Guardian, John McTernan claims it is “so obvious that it is rarely said,” that “everyone in the Labour Party wants to see a world free of nuclear weapons.” The Green Party’s Caroline Lucas meanwhile laments the “pervasive warped logic […] at the heart of every government’s defense policy since 1945.”

Such is the conviction that a nuclear-free world would be some kind of improvement. But if we are to turn back the clock, it is surely worth exploring the origins of such enduring logic. As history so amply demonstrates, we are much nearer the peaceable utopia that moralists agitate for with nuclear weapons than without.

Indeed, the history of the postindustrial but prenuclear world hardly makes for pleasant reading. Time and again belligerent world powers quite intentionally sent their working classes to die in the mud, faced with ever-more deadly weaponry. Only nuclear weapons have banished this kind of world-shattering conflict, the likes of which Europe was getting quite accustomed to before their advent.

Where this is challenged, it is with the charges that conventional military alliances like NATO, and European integration, also played a part. Antinuclear activists abhor the former, Corbyn and his ilk cannot abide by NATO and it seemed for a time they would turn on the European Union as well.

Now this is not to say that, should Britain disarm, great-power war would be upon us. War in Western Europe is virtually unthinkable and Britain would not immediately be much less secure.

But proper defense, the foundational responsibility of any state, requires thinking beyond the immediate: alliances are temporary, order is usually short-lived and promises ultimately amount to little.

Looking eastward, Britain is forewarned as nuclear-armed Russia preys upon formerly nuclear-armed Ukraine, the latter having traded away its nuclear arsenal in exchange for guarantees of nonaggression that turned out to be meaningless.

Fortunately, Britain also remains forearmed and together with every other power capable of wreaking conventional global annihilation helps uphold the delicate order between them. Yes, this is eyewateringly expensive, but as an insurance policy against the terrors of 1870, 1914 and 1939 it is unrivaled.

Labour’s recently demoted Michael Dugher, a victim of Corbyn’s reshuffle, speaks of the leader’s nuclear weapons review as “divisive and self-indulgent” — and what an exercise in self-indulgence it would be to have all the world’s other powers carry the baton while Britain sanctimoniously exempts itself.

Maintaining a minimum deterrent is the responsible policy of every great power. Most Britons and lawmakers recognize this, but still they needlessly abandon the moral high ground.

And to whom? To those who accuse us of being “stuck in the Cold War,” but whose cheery end-of-history worldview blinds them to the sordid reality? Those who are convinced that pacifism and nuclear deterrence are incompatible?

They may have the best intentions in the world, but they must not be allowed to wrench open the box we closed in 1952.