A wild read: "The most alarming of the intercepts revealed that one of the most senior Russian military commanders was explicitly discussing the logistics of detonating a weapon on the battlefield."

https://www.nytimes.com/2024/03/09/us/politics/biden-nuclear-russia-ukraine.html

"... soon the C.I.A. was warning that, under a singular scenario in which Ukrainian forces decimated Russian defensive lines and looked as if they might try to retake Crimea — a possibility that seemed imaginable that fall — the likelihood of nuclear use might rise to 50 percent or even higher."

“The more successful the Ukrainians are at ousting the Russian invasion, the more likely Putin is to threaten to use a bomb — or reach for it.”

"Administration officials said that the United States’ countermove would have to be nonnuclear. But they quickly added that there would have to be some kind of dramatic reaction."