Introduction Proliferation of nuclear weapons poses many threats to the international security. In response to such threats, nations look for ways of protecting their territorial integrity. The most effective mechanism of protecting individual national sovereignty entails adopting proactive response to security threats as opposed to reactive strategies (Nau 2008; Ross & Feng 2008). Deterrence is one of the proactive mechanisms of shielding a nation from violations of territorial integrity through acts such as terrorism in an international arena. This paper declares deterrence an effective strategy to prevent the proliferation of nuclear weapons to rogue states and international terrorists. First, it presents the theory of deterrence before discussing the challenges of proliferation of nuclear weapons and terrorism. Lastly, it justifies why deterrence constitutes an effective strategy of overcoming the problem of proliferation of nuclear weapons and terrorism. Deterrence The deterrence theory acquired immense recognitions in the cold war era. Its focus was on nuclear weapons. The strategy aims at dissuading enemies from taking destructive actions (Vasquez 2009, p.14). It also involves requesting other nations to stop doing things that are against other nations’ desires. Hence, it entails using threats as a means of convincing other nations why it is not in order to follow some paths. As a military strategist and a proponent of deterrence, Bernard Brodie claims that nations need to have credible and reliable nuclear deterrence to ensure that they are ready at all times, but not using the nuclear weaponry (Vasquez 2009). As quoted by Freedman (2004, p.43), Thomas Schelling presented the concept, ‘military strategy can no longer be defined as the science of military victory’. Rather, as a successful military strategy, he claims that deterrence encompasses coercion and/or acts of intimidation. In this extent, deterrence implies the capacity to harm other states that interact in the international arena in the effort to influence certain states to comply with the need to protect territorial integrity. The success of deterrence to curb any act of terrorism rests on the ability of a nation to deploy the power to hurt or harm other nations as a motivating factor for the target nation not to engage in any act that may harm the targeting nation (Waltz 2010). Proliferation of nuclear weapons in Iran evidences this assertion (Litvintsev 2014). The programme was initiated in the 1950s, with European governments and the US taking central roles. It was part of the programme of atoms for peace. The involvement of these two parties did not proceed for long since it was terminated during the close of 1970s when the Iranian Shah was overthrown by the country’s insurgency. In the mid 1980s, Khomeini regime brought up the idea of a nuclear programme in secret. The plan also encompassed preparing for acquiring the capacity to produce nuclear weapons that were initiated during the Shah’s reign. This move was initiated by the Iran’s devastation that had been caused by Iraq due to the moves of Iraq to deploy chemicals weapons in the war between the two nations. Conseque