Only two European countries – France and the UK, both NATO members – have nuclear weapons, and leading politicians have called for the UK and EU to maintain close military and security links post-Brexit. In the context of the Trident renewal debate and the UK government's recently published integrated defence and security review, this article uses data from the new UK Security Survey to analyse attitudes towards the possession of nuclear weapons among the British public. It assesses three key theorical strands in the wider scholarly literature on public opinion and states’ use of military force: domestic political attitudes, foreign policy predispositions, and the ‘gender gap’. We find that all three theoretical perspectives contribute to the underpinnings of contemporary public opinion towards nuclear weapons. Support for the retention of Britain's nuclear deterrent is associated with being a Conservative Party supporter, favouring Brexit, endorsing superior military power worldwide as an important foreign policy goal, wanting to protect the transatlantic relationship, and with being male. The article makes a distinctive contribution to the growing subfield of research on public opinion and foreign policy, while the findings advance wider empirical understanding of contemporary citizen engagement in a key dimension of security policy.