Despite the militaristic title, it's not about aggression or destroying your enemies. Throughout the book, open warfare is always depicted as the most costly and least desirable option. Adding an enemy's strength to yours, with zero destruction, is regarded as the ultimate form of victory.
http://www.thefreedictionary.com/destroy
de·stroy (d-stroi)
v. de·stroyed, de·stroy·ing, de·stroys
v.tr.
1. To ruin completely; spoil: The ancient manuscripts were destroyed by fire.
2. To tear down or break up; demolish. See Synonyms at ruin.
3. To do away with; put an end to: "In crowded populations, poverty destroys the possibility of cleanliness" (George Bernard Shaw).
4. To kill: destroy a rabid dog.
5. To subdue or defeat completely; crush: The rebel forces were destroyed in battle.