In an interview at the end of last week, the Iranian ambassador to the United Nations said that his country’s nuclear enrichment “will never stop” because it is allowed for “peaceful energy” purposes. This is the latest development in the escalation of tensions on the Iranian nuclear program, which erupted when Israel targeted the country’s nuclear facilities in June. To understand the reason for the importance of enrichment, Madeleine Vinlai talks to Robin Graims, a professor of material physics at Imperial College in London. He explains what goes to the creation of a nuclear weapon, and why access to the arms stage is very difficult
