You might be interested in some previous posts on moral judgement passed on Alexander the Great:

• How did Alexander the Great become known as an exemplary person, but other conquerors are viewed in a more dubious or negative light?
  ^([2014 Dec. 13 | 123 comments])
  ^(/u/XenophonTheAthenian dissects changes in historiography on Alexander from Antiquity to the 20^th century.)

• When I was younger I liked to think of Alexander the Great as a noble figure who wanted to unite the world and erase the differences between peoples. The more I think about it though, the more he seems to resemble a mere Hitler-like dictator. Is there any nobility in the historical Alexander?
  ^([2013 Jan. 16 | 146 comments])
  ^(/u/Daeres analyzes Alexander's actions and accomplishments in context with the morality and actions of his contemporaries and other ancient rulers.)