A sharp public clash over whether Britain should arm for war with Russia or push for a deal — bad news for anyone hoping the nuclear risk is being taken seriously in London.

• British hawks say the country must get ready for war, arguing that looking strong is what stops an invasion.
• The counter-argument: the fighting itself is what brings the world close to a nuclear exchange, and backing off would make a Russian strike less likely.
• The Hitler comparison is doing a lot of the work on the pro-war side — the claim that weakness in the 1930s invited attack.
• The debate turned ugly over Hiroshima and Nagasaki, with the hawkish side defending the killing of children as justified to end a war.
• Underneath it all is a flat refusal to accept that Russia might ever use nuclear weapons first.

Outlook: Expect this argument to keep hardening on both sides as Britain talks up war readiness and the risk of escalation stays unresolved.