Sri Sri Ravi Shankar:
The whole essence of the Gita is to act without being attached to the action. It's all about yoga, not about war but your attitude. When you are faced with a situation like war, how do you manage yourself? The worst situation in life is when you have to face a war and when you have to fight not with an enemy, but with some of your own people. When you have to fight with your own brothers and sisters, how do you handle the situation? It's easy to fight a war with an enemy, someone you don’t like. But fighting with someone who is part of your own family is the worst thing.
If you can manage your mind in the worst scenario, then you can manage yourself in any situation. Given the extreme example of how you can manage the mind, the consciousness, yourself, that’s the whole essence of the Gita, not the war. Skill in action is yoga.
A similar knowledge was taught by Ashtavakra, in the palace. When your spirit is very high and you want liberation, that was Ashtavakra's state. And when your spirit is so low, totally desperate, completely broken and depressed, that was Arjuna’s state. At that time the same knowledge of the Self was given to him in the Bhagavad Gita.