The main point of that quote is that a battle is a negative-sum game. Reaching the same ultimate outcome without a battle is better than fighting for it, because both sides will suffer losses in the battle.
Trying to achieve a lasting peace through a decisive victory rarely works, because people don't work like that. In a more likely outcome, you are simultaneously not aggressive enough to prevent future conflicts and too aggressive, creating enemies motivated by revenge. Revenge is a dangerous motive, because it can turn battles into positive-sum games. Any enemy losses – both combatant and civilian – become victories, while your losses only matter by reducing your ability to kill more enemies.
Agreed, and to add, I never understood that the old "war texts" were supposed to be detailed workflows for war and more just stating in plain language from people who've fought wars knew for the general public to understand. I've not read the old war texts since I was forced to in High School, but my takeaway from books like Art of War and The Prince was the authors trying to shatter the concept of Romantic wars with the boring reality of everything that comes with war.
That is, I understood that the point of the books was more to get governments and people to engage with understanding the practical elements of war, like:
- Wars are very very very expensive
- They're expensive even when you're not at war
- Your troops probably don't want to be fighting cause it means they probably will get hurt or die
- No one likes being conquered, so don't assume that the war is done once you've killed enough soldiers
- It's really expensive to supply an army
- Seriously, do you know how much a horse eats? How about a thousand horses?
My takeaway from the books was first teenage disappointment that the books weren't super deep or evil like I had been led to believe, and second that the books really seemed to try to deglamorize war by talking about all the stuff involved with it besides the killing/conquering, and showing how expensive and exhausting it really is.
Yes, those are the main points. Sun Tsu realized that war is a terrible thing, especially the human suffering. He wrote "Art of War" to admonish rulers to understand and avoid war.
All of that depends on your goals and priorities. And keep in mind, not everyone fights a battle for defensive reasons. Peace isn't always the desired outcome of war.
He also implies that diplomacy and posturing is actually part of battle which isn't the case but I am sure diplomats and politicians consider themselves warriors.
Often wars are started to avenge a wrong, significant losses in your side were accepted when you declared war. If you win a battle without accomplishing your objectives then what was the point?
But I think I do agree with you on his intent and that is sort if my point, his wisdom is neither absolute nor infallible. I would consider it a guidance to help you decide not hard set commandments to follow.
Trying to achieve a lasting peace through a decisive victory rarely works, because people don't work like that. In a more likely outcome, you are simultaneously not aggressive enough to prevent future conflicts and too aggressive, creating enemies motivated by revenge. Revenge is a dangerous motive, because it can turn battles into positive-sum games. Any enemy losses – both combatant and civilian – become victories, while your losses only matter by reducing your ability to kill more enemies.