This article presents a brief overview of the state-of-the-art in large language models (LLMs) like ChatGPT and discusses the difficulties that these technologies create for educators with regard to assessment. Making use of the 'arms race' metaphor, this article argues that there are no simple solutions to the 'AI problem'. Rather, this author shows that educators and universities will need to adopt a complex strategy consisting of solutions at four different levels of vulnerability: Ethical, pedagogic/didactic, technological and policy. Lastly, the article presents general recommendations for addressing vulnerabilities at each of these levels.