> Nobody wants World War 3. ... the alternative, full-blown war across Europe and the potential for nuclear bombs being used is unfathomably worse for everyone both inside Russia and outside.

We may get it by mistake. A wider war in Europe is all too likely. The NATO countries and the EU are shipping large amounts of military supplies into Ukraine. One story mentions 17 US widebody cargo aircraft per day going into Poland. This is a real threat to Russia's attacks, because the supplies include the good anti-tank and anti-aircraft weapons. That leaves the Russian army fighting as infantry against a much larger armed population, a long, bloody slog. Unless Russia can cut off outside supplies, there's no path to victory.

It's all too likely that some attempt to attack Ukranian supply lines will reach over the border into a NATO country. Just some Russian pilot in Ukraine in a fight making a turn too slowly could result in overflying Polish territory. Where the air defenses are ready to shoot down anything hostile.

Re-read how WWI started. Everybody had mutual-defense treaties, and one minor event set it all off.

2 hours ago: "Putin says sanctions introduced on Russia are equal to a "declaration of war"" - CNN.