Starting from the decline in intentional homicide in Mexico during 2023, this article analyzes the roots of the violence crisis that has plagued the country for more than fifteen years. It seeks to answer the question of the factors, events, or conditions that triggered homicidal violence in Mexico starting in 2007. The article collects the main hypotheses proposed on this issue and reviews their explanatory scope. These hypotheses are divided into three groups. The first consists of government actions that had unintended effects. These include the deployment of military operations in various regions of the country starting in December 2006, the implementation of the kingpin strategy, which involves targeting and arresting high-level drug cartel leaders, and the tightening of drug interdiction mechanisms for drugs coming from South America. The second group consists of specific events related to the proximity to the United States. These include the increase in ex-convicts deported from the United States, the rise in the number of firearms coming from the United States, and the increase in the price of cocaine. Finally, references are made to more structural conditions that preceded 2007. Specifically, political alternation and the crisis of local order manifested by the poor state of local police forces and long-term socio-economic explanations. To bring the discussion to the present moment, specifically to the year 2023, the last part of the text offers a reflection on the persistence of these factors and the future challenges that Mexico faces. This section focuses on two issues that are added to the topics reviewed in the first part of the article: the wave of migration that spread throughout 2023 and the incursion of fentanyl into the national drug market, which was exacerbated in the years following the COVID-19 epidemic.