Addressing the physical and psychological realities of the operational theatre and arming those serving in mission command and control roles with sound tenets of national and international security, have always been essential to military professionalism. As humanity ventures further into space for productive endeavors, the ethical considerations surrounding military space operations will become increasingly complex, and ever more necessary. We propose and argue that military space ethics would commendably pursue ambitious programs that jointly target global security, international stability, and space habitability. The unique environment of space demands a cogent and prudent ethical framework prepared for the expeditionary nature of all missions, civilian and military, aiming at cultivating the vast rewards of space investment. Integrating principles of military ethics and cosmopolitan ethics within a structural-functional framework would permit responsible strategies that safeguard national security together with global well-being.