In what appears to be an emerging trend, terrorism is increasingly perpetrated by groups with a dominant religious component, in contrast to the largely politically oriented groups of the past two decades. The political groups have not significantly changed their strategy and tactics and appear to act under self-imposed restraints. However, terrorism motivated by a religious imperative has shown itself to be considerably less discriminate than terrorism motivated by ostensibly political aims. It is also based on significantly different ethical values. As a result, it involves a far wider choice of targets and of victims. Distinctions based on ideological contrasts or on nationalist or irredentist aims no longer usefully describe the way that terrorists justify their violent campaigns. The causal link between the predominance of religion-based terrorism and terrorism's growing lethality is reinforced by the data showing that although Shi'a Islamic groups committed only 7 percent of all international terrorist incidents since 1982, those incidents are responsible for 21 percent of the total number of deaths. Footnotes.