<p>This paper presents a novel philosophical analysis on the harmful effects of LLM AI chatbots (AI companions) used by children in the United States. The author of this paper develops and defends The Consistency Argument for Protecting Children from AI Chatbots (The Argument from Consistency for short), which concludes that the government is justified in restricting children from using AI chatbot companions. The key move in the argument is as follows: if one accepts that the harms caused by exposing children to pornography justifies the current laws that prohibit and punish the transmission of pornography to children, and there is strong evidence that comparable or worse harms result from AI chatbots used by children, then the government is also justified, <i>mutatis mutandis</i>, in similarly restricting children from using AI chatbot companions. Evidence demonstrating the harm from chatbots includes detailed accounts of three recent case reports of teens whose suicides, self-harm, and sexual abuse resulted from their interactions with AI chatbots, in addition to recent studies in the scientific literature that identify and quantify the risks of harm posed by chatbots. After demonstrating that The Argument from Consistency is both valid and sound, the author argues in favor of federal legislation that strictly regulates the age of chatbot users, along with both civil liability and severe criminal punishments for companies or individuals that violate the law. The author concludes this paper by considering the three strongest objections to this argument and then showing that each objection is unsound.</p>