This was the intel shared with the Poles, Scandinavians and Balts a few months back -- and met with a fair degree of skepticism, as I was told. It was then leaked in the Polish media and caused quite a stir in Polish defense circles.
The more probable threat scenarios laid out here -- cyberattacks, sabotage operations and drone swarms -- aren't just hypothetical; they're happening now. (See the latest drone incident in Leipzig.)
Note this, however: "The likelihood of the most extreme scenario—a limited land incursion—is low, but gets higher as time goes on, according to the reports."
A "limited land incursion" is an invasion of NATO territory. That would either put Russia in a state of open war with the alliance or simply end the alliance in the event that Article V went unhonored (what the Russians would most want to happen). This applies with or without U.S. participation. I'd imagine Ukraine would also participate in a second front under such circumstances, not only in common cause but to relieve pressure along the contact line at home.
The skepticism was rooted in the belief among Eastern Flank partners (and, as always, there were disagreements among them) that Russia couldn't afford to test Article V's integrity given its struggles on a non-NATO battlefield. Perhaps views among those partners have shifted in light of reported U.S. shortages of critical munitions. That reporting and the timing of this leak don't seem coincidental.
The Wall Street Journal (@WSJ)
Exclusive: Russian President Vladimir Putin could try to test NATO’s resolve with a limited assault on an allied country in the next few years, according to new U.S. intelligence reports on.wsj.com/45brda4
Link
Exclusive | U.S. Intel Finds Putin Could Test NATO’s Resolve With Limited Incursion
The new assessment updates past forecasts that Russia’s leader wouldn’t provoke the alliance during the Ukraine war.
wsj.com
— https://nitter.net/WSJ/status/2085534107845427688#m