It is not necessarily obvious how a shadow war will end, even during the waging of it. In 1950, the West had no idea that the Cold War would end 25 years later with the Helsinki accords, 39 years later with the fall of the Berlin Wall, or 44 years later with the fall of the Soviet Union. Similarly, we cannot know today how the war against Islamic jihadism will end, or how clear it will be when the end comes that it has come. Nevertheless, the very ambiguity of this war makes it all the more important to debate the question of victory conditions. There will be no surrender ceremony on a battleship or signing of a cease fire agreement, so we need to know what to look for instead.
The entire post is a valuable discussion of the entire subject including the probable motivations of those opposing this so called "shadow" war.