When is the use of military force justified?

This isn't my opinion, but when the use of military force is justified, iswhen all attempts to resolve an issue have been made and resolution peacefully is not possible. In the case of terrorist actions against a government, whereas the terrorist organization is not willing to subdue to peaceful resolution, the use of military force is not only justified but as well necessary. The preservation of peace always has and always will rely on some military force being used to protect against massive horrific attacks on all people of the world.

Ithink your answer is the last one