The prevailing assumption in the Israeli and international media, and among governments around the world, is that the assassination of the head of Iran’s military nuclear project, Mohsen Fakhrizadeh, was carried out by Israel. If so, the costs and benefits of the assassination from Israel’s vantage point should be examined and weighed. To this end, certain questions must be answered: What was the strategic purpose of this action, and what is the likelihood of its ultimate success? In light of this goal, was the timing of the action correct? And finally, are the potential costs greater or smaller than the expected benefit? This article concludes that in the case of the killing of Fakhrizadeh, it is doubtful that the benefits outweigh the costs, and unclear that the assassination will substantially serve the goal of damaging and delaying the Iranian nuclear program.