Talk of using nuclear weapons against Iran has entered mainstream US political debate, a dangerous escalation in a war already going badly for Washington.

• Marjorie Taylor Greene said White House strategy meetings have discussed nuclear strikes on Iran; the White House denied it.
• Conservative media voices close to Trump are pushing for ground troops and hinting at atomic bombs, comparing Iran to wartime Japan.
• US intelligence reportedly told Trump that Iran was nowhere near building a nuclear weapon.
• Israel is seen as at least as likely to reach for a nuclear option, having burned through its missile interceptors during 40 days of fighting.
• There is no such thing as a small or "tactical" nuke — any use would break an 80-year taboo and change how nations fight.

Outlook: With conventional options failing and Iran holding leverage over the Strait of Hormuz, pressure to escalate keeps building rather than easing.