Is fighting justifiable till there is no more mischief and the way of life prescribed by God is established?

Verses 39-40 of Chapter 8
O Believers, fight with the disbelievers till there is no more mischief and the way of life prescribed by Allah is established in its entirety. Then if they desist from mischief, surely Allah beholds what they do, but if they give no heed, know it that Allah is your Protector, and He is the best of all protectors and helpers.