Leaked Pentagon documents show the US is building nuclear strike options for Trump in the Iran war — a dangerous escalation with almost no political pushback.

• Internal Pentagon papers describe expanding the president's nuclear options in the Iran conflict, with Under Secretary Elbridge Colby driving the push.
• Trump again threatened Iran's existence, saying it either signs a deal or "won't exist any longer."
• The Senate was briefed earlier this month and said nothing — including top Democrat Jack Reed.
• Calling the weapons "tactical" or "limited" is spin; any nuclear strike would kill huge numbers of civilians and leave radiation for decades.
• The pressure comes from a war the US can't exit: American and Israeli missile defenses are running low, and a nuclear threat is being floated as the shortcut to forcing Iran to surrender.

Outlook: Expect the idea to be normalized in official statements and media coverage before any decision, with 92 million Iranians in the line of fire if it goes further.