For the topic:
i) It is important for a ruler to win war because it makes him more powerful.
ii) It gives him prestige and fame.
iii) It proves the strength of the ruler.
iv) It gives more revenue.
v) It helps in the extension of his empire.
Against the topic:
i) War has never provided a pleasant sight to anyone; it has always been devastating for the armies and their family.
ii) It brings massive loss of life.
iii) The ruler who fails to win the war, has his reputation, his empire at stake (endangered).
iv) When defending itself against another country, a nation never lacks men, but too often, soldiers.
v) Disaster establish indestructible bonds between armies and their commanders.