Wow. If i have come across the best outline for this essay, its this one. When i looked at the topic for the first time, I sketched an imaginary outline almost same as yours.

Most aspirants didnt consider the other side of the topic - Great nations DO engage in fight/wars if its a requirement of the time.

Plus the fight against evils that you mentioned - Though most people elaborated the Nation versus Nation fight, the perspective - that a nation has to fight against many things internally too to become great- is a desperate requirement to score in the 50's or 60's band.