important symbolic acts such as the blood sacrifice link acts of violence to religion and terrorism. suicide terrorism, self-sacrifice, or martyrdom has throughout history been organized and perpetrated by groups with both political and religious motivations. the christian tradition has a long history of heterodoxical and heretical groups which stressed self-immolative acts and scholarship has to some degree linked this to modern political groups such as the irish republican army. suicide terrorism or martyrdom is efficient, inexpensive, easily organized, and extremely difficult to counter, delivering maximum damage for little cost. the shocking nature of a suicide attack also attracts public attention. glorifying the culture of martyrdom benefits the terrorist organization and inspires more people to join the group. according to one commentator, retaliation against suicide attacks increases the group's sense of victimization and commitment to adhere to doctrine and policy. this process serves to encourage martyrdom, and so suicide terrorism, self-sacrifice, or martyrdom represent "value for money". robert pape, a political scientist who specializes in suicide terrorism, has made a case for secular motivations and reasons as being the foundations of most suicide attacks, which are often labelled as "religious".