My main character have a moral dilemma

He is a captain of a battleship. His race had been fighting an ancient race of robot for hundred of years, so long that no one can remember who started the war or what it was about. During a decisive battle, his ship is task with carrying a super weapon that could end the war.The dilemma is that if he use it, it would also destroy all of the robot, possibly commit genocide against an intelligent race, but if he not, he will indirectly responsible for the death and destruction the war will cost if it continue.

Tell me what do you guys thing of it.

A good dilemma that could be used to seed a good story. I predict that the weapon will be used as leverage to force diplomatic talks to occur, and at least one sabotage subplot concerning the weapon.