Given the widespread relief accompanying Joe Biden’s transition to the White House, it seems churlish to start picking apart his policy agenda. Yet, there are grounds for concern about how the incoming administration will reshape US nuclear weapons policy over the next four years. As a presidential candidate, Biden signalled that, if elected, he would roll back the Trump administration’s introduction of lower-yield nuclear warheads on the US Navy’s submarines, and embrace a nuclear “No-First-Use” commitment. No-First-Use is a declaratory pledge not to initiate the employment of nuclear weapons in a conflict, and limits the role of nuclear weapons to countering the adversary’s use of nuclear weapons. The Obama administration came close to endorsing it on two separate occasions – during the 2010 Nuclear Posture Review, and in 2016 as part of a subsequent review of US nuclear policy. Despite that Barack Obama ultimately rejecting this shift in US nuclear policy, then Vice President Biden remained sympathetic to a No-First-Use commitment.