Yet once they have defined their national interests in terms of nation security, they can draw back from their outlying positions, located close to, or within, the sphere of national security of the other side, and retreat into their respective spheres, each self-contained within its orbit. Those outlying positions add nothing to national security; they are but liabilities, positions that cannot be held in case of war. Each bloc will be the more secure the wider it makes the distance that separates both spheres of national security. Each side can draw a line far distant from each other, making it understood that to touch or even to approach it means war. What then about the interjacent spaces, stretching between the two lines of demarcation? Here the fourth rule of diplomacy applies