Sri Aurobindo’s attitude is summarized in his saying, “Reason was the helper; Reason is the bar”

[The genesis of Just War within the overall rubric of Hinduism as a philosophy can be traced back to the oldest religious and philosophical books of mankind, the Vedas. Take for example, the Rig-Veda, the oldest written book. It is but a collection of hymns, to a variety of old Hindu Gods, and therein you will find a very large collection of hymns which pray to various God(s) to intercede in times of war and help in winning battles. So whether one is praying to Indra, the Lord of Heavens or Agni, the Lord of Fire, it is your basic prayer before war...But the knowledge of the Vedas and Upanishads was distilled into the Mahabharata, the gigantic and profound Hindu epic and one can legitimately claim that the Mahabharata was itself distilled into the Srimad Bhagwat Gita... Just War - Theory and Practice
from Desicritics by Dr Bhaskar Dasgupta]

This ably accomplished round-up of war and non-violence misses the evolutionary angle that has been envisaged by Sri Aurobindo. The touchstone for judging any action is whether it supports the future evolution of humanity or tends to hinder it. This teleological demand is often disregarded by superficial views. Sri Aurobindo’s attitude is summarized in his saying, “Reason was the helper; Reason is the bar.” Gandhi’s non-violence was moralistic and rational but at some point its rigidity turned out to be fetters.

Further clarity in the matter can be deduced from the three positions vis-à-vis Hitler. Netaji Subhash colluded with him; Savarkar supported his policies. The Congress bargained with the British using him as an alibi. But Sri Aurobindo was forthright in his opposition because Hitler, he thought, represented a roadblock to evolution. It is not difficult to locate similar contradictions marauding the present day hot spots upon the Globe. [TNM]