"In the 21st century we have seen a tendency toward blurring
the lines between the states of war and peace. Wars are no longer
declared and, having begun, proceed according to an unfamiliar template.
The experience of military conflicts — including those connected with
the so-called coloured revolutions in north Africa and the Middle East —
confirm that a perfectly thriving state can, in a matter of
months and even days, be transformed into an arena of fierce armed
conflict, become a victim of foreign intervention, and sink into a web
of chaos, humanitarian catastrophe, and civil war."
No more one side lining up and another side lining up to oppose. The distinction of what is war and what is not gets blurred, like in Ukraine right now. Won't be pretty.