This paper examined insecurity as a social problem in Nigeria. A case studies methodology was used for data analysis. Secondary sources such as books, journals, internet sources, and newspapers were utilized for data collection. The finding shows that insecurity is a major social problem in Nigeria that has affected the social and economic wellbeing of the people. It has placed Nigeria’s national security on a red line in that the government, which is supposed to protect the people, is finding it difficult to deal with insecurity occasioned by terrorism, armed banditry, kidnapping, and the farmers–herders conflict. Insecurity is the manifestation of bad leadership, lack of true federalism, corruption, injustice, and failure to reform the nation’s security system coupled with politicization and polarization of the intelligence and security architecture.