[richardw]

Firing a nuke at Ukraine is the huge escalation you’re looking for. After that, options are: nothing, slap on the wrist, gauge the response enough to prevent repetition, escalate.

The first two guarantee that any time Russia wants more land she simply needs to first place her finger on a tactical nuke button, and then take the land.

The US hasn’t said it would sink the fleet, retired generals have. Any rational negotiator will keep all options on the table and only limit them when it’s time to act.

The real outcome might well be to not attack in response, which would generate nationalist instincts in Russia and support from the murkier countries of the world. Rather isolate the hell out of Russia, turn off their internet, fling them back to the social Stone Age. Cut roads, rail, sea links. Include Ukraine into Nato asap to prevent any repetition.