Objective reality
Whether or not Kyiv can ultimately triumph over Moscow depends on how exactly it chooses to define victory
Victory in war is sometimes easy to define. World War II ended with Allied troops in control of Berlin and Tokyo, and with the German and Japanese leadership removed. The Vietnam War, on the other hand, ended in a clear defeat for the United States: North Vietnam conquered South Vietnam despite the futile expenditure of 58,000 American lives. The Korean War is sometimes called a stalemate because it never formally ended.
If Ukraine aims to maintain its independence as a democracy linked to Europe, while reserving its right to the ultimate return of its territory, victory remains possible.