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I'm Helena Merriman, and in a new BBC series,
I'm talking to the reporters who first covered this story.
What did they miss the first time?
The History Bureau, Putin and the apartment bombs.
Listen on bbc.com or wherever you get your podcasts.
Welcome to the Inquiry from the BBC World Service.
I'm Charmaine Cosier.
Each week, one question, four expert witnesses, and an answer.
February 2026 That's the expiry date of the New Strategic Arms Reduction Treaty or New START.
It's the last remaining Nuclear Arms Control Treaty between Russia and the US.
Beyond that bilateral agreement, some countries are expanding their nuclear weapon collections.
States that don't have them are considering getting them.
So this week we're asking Is nuclear disarmament set to self-destruct?
Part 1 Going Nuclear Well, it all started during the Second World War.
When the great powers involved tried to do everything to win this war.
And the development of nuclear weapons was one method.
My name is Hermann Wenzka.
I'm Head of Department of the Berlin Department of the Institute for Contemporary History and I'm Professor for Modern History at the University of Potsdam.
A number of states worked on such projects during World War II,