Why Sweden Is Rethinking Nuclear Weapons

A country that hasn't fought a war since 1814 just dropped a bombshell. Sweden, the nation that stayed neutral through two world wars, is now discussing nuclear weapons with Britain and France. When a country synonymous with pacifism starts talking nukes, something fundamental has shifted.

Ulf Kristersson, Sweden's Prime Minister, put it bluntly at the Munich Security Conference: "We are freshmen within all the nuclear planning of NATO," but Swedes take that planning "very, very seriously." This from a country that once had Europe's most prominent anti-nuclear movement and joined NATO just two years ago.

The Trust Deficit

The story begins with broken promises. After World War II, Sweden actually started developing nuclear weapons to deter Soviet invasion. But in the 1960s, Washington pressured Stockholm to abandon the program, offering reassurances about America's nuclear umbrella instead. Sweden trusted that promise so completely it signed the Nuclear Non-Proliferation Treaty in 1968.

Today, that trust is cracking. Germans have coined a term for it: Vertrauensverlust — "loss of trust." Swedes call it förtroendeskadligt — "damaging to trust." Kristersson captured the mood perfectly: "We haven't broken up, but we watch and listen carefully, and we are aware of the fact that we can be surprised suddenly, and we do not like that."

The erosion isn't theoretical. As the Trump administration bullies allies and threatens to seize sovereign territory, America's security commitments have become a devalued currency. The 80-year nuclear umbrella that shielded Europe suddenly feels less reliable.

Europe's Nuclear Awakening

Enter Britain and France, Europe's only nuclear powers. Last summer, their leaders made an unprecedented pledge: coordinate nuclear planning and respond jointly if Europe faces extreme threat. It was the first time European nuclear powers committed to collective deterrence.

Now the conversation is expanding. German Chancellor Friedrich Merz revealed talks with French President Emmanuel Macron about a "collective European nuclear deterrent," declaring that U.S. leadership "is being challenged, maybe even already lost." The rules-based international order, he added, "no longer exists."

Sweden's participation marks a stunning reversal. This is the country that led Europe's anti-nuclear movement in the 1970s and '80s. But as Kristersson put it with stark realism: "As long as bad powers have nuclear weapons, democracies also need to be able to play."

The Ukraine Lesson

The war in Ukraine crystallized European thinking. Ukraine gave up nuclear weapons inherited from the Soviet Union in exchange for security guarantees from Russia, the U.S., and others. Those guarantees proved worthless when Putin invaded.

Kristersson predicts the war's outcome will determine Europe's nuclear trajectory. The more favorable the result to Russia, the stronger the case for European nuclear deterrence becomes. It's a lesson in the brutal mathematics of international relations: promises matter only when backed by credible force.

Washington isn't pleased. Elbridge Colby, undersecretary of defense for policy, told the Munich audience that America doesn't support "friendly proliferation." But as the U.S. simultaneously pressures allies to do more while threatening to do less, such warnings ring hollow.

The New Nuclear Reality

The numbers tell the story. The New START treaty, the last significant nuclear arms control agreement between the U.S. and Russia, expired this month. Meanwhile, Russia's nuclear threats over Ukraine have normalized once-unthinkable discussions about nuclear warfare in Europe.

Sweden isn't talking about building its own bombs—yet. Kristersson emphasized leveraging "friendly powers'" capabilities rather than domestic development. But when asked if he could rule out the kind of proliferation Sweden nearly pursued after World War II, his answer was telling: "Can I exclude it for eternity? Of course I cannot."