In November 2016, the Cook County Board of Commissioners passed a tax on sugar-sweetened beverages (SSBs) in a razor-thin 9-to-8 vote. In October 2017, after two months in effect, the tax was repealed in an overwhelming 15-to-2 vote. In this paper we use interviews with politicians, advocates, and opponents to construct a detailed narrative of the events that transpired and track the discourse around the tax by analyzing public comments and news coverage. We then contrast these findings with established best practices for passing SSB taxes to identify a set of factors that reduced the tax’s political viability. Keeping in mind Cook County’s hostile tax climate and the influence and resources of the beverage industry, we focus our analysis on the following government actions that diminished public support for the tax: (a) the near-failure to implement an unnecessarily complex tax design within legal and technical constraints, (b) the failure to dedicate sufficient time and resources to a health education campaign before the tax was introduced, and (c) the public presentation of the tax as an effort to balance the budget, instead of as a measure to improve the health of the county. We conclude with a series of considerations for policymakers attempting to introduce soda taxes in other jurisdictions.