Trends in international and domestic terrorism in Western Europe, 1968–1988

An assessment of the problems related to trend analysis on international and domestic terrorism during two decades, beginning in 1968, including definitions, data collection, and sources, shows that propositions on terrorism in general are almost impossible to make and are not very useful for policy‐making. Nevertheless conclusions are drawn about the number of incidents, number of casualties, types of incidents and target selection. Particular emphasis is placed on the margins of error and the differences based on the various data collection efforts. While the first part concentrates on terrorism on a global scale, the second part deals with Western Europe in particular. Overall and national trends are provided for number of incidents, casualties, incident type, active groups and their tactics and target selection. Special attention is given to the spill‐over effect from the Middle East and the selection of American targets. It is almost impossible to indicate an overall trend for Western Europe. Various European countries experienced and continue to experience severe domestic terrorist problems which in some cases appeared to be far more destructive and lethal than international terrorism. A major conclusion is that researchers should be very careful with trend analysis on empirical data of terrorism, particularly on domestic terrorism. The trends vary from country to country depending on their specific political problems.