Russia's war in Ukraine is undoubtedly being studied very closely, and will be analyzed for years to come. This essay, and the longer chapter linked within, make up part of the International Institute for Strategic Studies' Strategic Survey 2022, an excellent survey of recent world events relevant to security studies. No one knows the eventual outcome of this war, but the human and economic effects are clearly devastating. This has grown to be the largest war in Europe since 1945, involving not only two large states but many other nations providing support. Although Ukraine's allies are taking pains to deter Russia from escalating the conflict with the use of nuclear weapons, the implicit threat remains. This article, and the longer chapter, provide excellent insight into the emerging military lessons from Russia's war in Ukraine.
"Russia's War in Ukraine: What Are the Emerging Military Lessons?" - International Institute for Strategic Studies
"Perhaps the most important facet of the war is that what was planned as a short 'special military operation' against an inferior enemy has turned into a large-scale conflict between states, in which prolonged fighting has been at a high intensity and over a wide geographical area."
https://www.iiss.org/blogs/analysis/2023/01/strategic-survey-2022-russias-war-in-ukraine
