In this work we attempt to develop models that can suggest requisite levels of investment, and/or indicate the strategic nuances of such investments in the face of possible cyber terrorist attacks. Beginning with one naïve model each under the two broad conceptual frameworks of Decision Theoretic and Game Theoretic frameworks, we have incrementally introduced pertinent backgrounds, investment criteria and economic dynamics to achieve (what we call) adequate investment models for countering cyber terrorism related attacks. This initial work is geared towards a broad based understanding of the issues surrounding the threat of cyber terrorism, and an adequate investment propensity of the defender.