Jihadists have their nasheeds, and the Islamic State (IS) became popular for its nasheed compositions used in propaganda videos. Nasheed is an a cappella song praising the Prophet Muhammad and reciting Quranic verses glorifying jihad. Similarly, drug cartels have bands that compose and sing Narco Corridos, or “drug ballads,” based on Mexican folk-music, which glorify cartel leaders as modern day “Robin Hood” figures, and announce executions of enemies. Both nasheeds and narco corridos have much in common: glorifying historical victories over enemies in wars and revolutions; using lyrics to warn their enemies about their invincibility and strength and bravery; calling out specific enemies as targets; and using their respective ideologies to justify their acts, behavior, and beliefs. This study examines and comparatively analyzes the two musical genres in the context of terrorism and narco-terrorism, and how they affect their respective followers, admirers, and devotees. The analysis also highlights how these musical genres popularize crime and violence, and de-sensitize audiences to the extreme brutality that they praise and glorify in their songs. There are some contextual distinctions that separate the two genres as well, and they entail part of the comparative analysis. The use of social media in both contexts is an essential tool to popularize nasheeds and narco corridos; they use YouTube videos, Twitter and Facebook, and other Internet resources to spread their music and messages. How have governments responded to these social and religious musical media? What are the implications of these for counter-terrorism and counter-narcotics strategies? These are some of the questions that this study addresses.