Essentially, the US wants Russia to stand down from its signaled intent of possibly using tactical nuclear weapons if NATO’s reportedly 100,000-strong invasion force crosses the Dnieper, which could occur if Russia achieves a military breakthrough…

Polish Foreign Minister Radek Sikorski revealed in his latest interview with The Guardian that “The Americans have told the Russians that if you explode a nuke, even if it doesn’t kill anybody, we will hit all your targets [positions] in Ukraine with conventional weapons, we’ll destroy all of them. I think that’s a credible threat.”

https://www.zerohedge.com/geopolitical/us-playing-dangerous-game-nuclear-chicken-russia