This article postulates a theory of information warfare within the larger context of warfare and proposes ways to wage information warfare at the strategic and operational levels. The tools to wage information warfare are at hand, and because information weapons are such powerful weapons, both combatants and noncombatants need to be protected against them. The vulnerability to information warfare is universal. The decisions to pursue the development of information weapons or to prosecute information warfare are governmental decisions. These decisions need to be made consciously and deliberately and with an understanding of the moral and ethical risks of information warfare. After assessing all the risks and deciding to create information weapons or engage in information warfare, the decision makers should first have an understanding of these weapons and a weapon employment theory before such warfare starts rather than after the weapons are deployed or have already been employed. The United States should expect that its information systems are vulnerable to attack. It should further expect that attacks, when they come, may come in advance of any formal declaration of hostile intent by an adversary state. When they come, the attacks will be prosecuted against both knowledge systems and belief systems, aimed at influencing leadership choices. The knowledge and beliefs of leaders will be attacked both directly and indirectly. Noncombatants, those upon whom leaders depend for support and action, will be targets. This is what we have to look forward to in 2020 or sooner.