Since 1900, terrorists' motivation, strategy, and weapons have changed to some extent. The anarchists and the left-wing terrorist groups that succeeded them, down through the Red Armies that operated in Germany, Italy, and Japan in the 1970s, have vanished; if anything, the initiative has passed to the extreme right. Most international and domestic terrorism these days, however, is neither left nor right, but ethnic-separatist in inspiration. Ethnic terrorists have more staying power than ideologically motivated ones, since they draw on a larger reservoir of public support.
The greatest change in recent decades is that terrorism is by no means militants' only strategy. The many-branched Muslim Brotherhood, the Palestinian Hamas, the Irish Republican Army (IRA), the Kurdish extremists in Turkey and Iraq, the Tamil Tigers of Sri Lanka, the Basque Homeland and Liberty (ETA) movement in Spain, and many other groups that have sprung up in this century have had political as well as terrorist wings from the beginning. The political arm provides social services and education, runs businesses, and contests elections, while the "military wing" engages in ambushes and assassinations. Such division of labor has advantages: the political leadership can publicly disassociate itself when the terrorists commit a particularly outrageous act or something goes wrong. The claimed lack of control can be quite real because the armed wing tends to become independent; the men and women with the guns and bombs often lose sight of the movement's wider aims and may end up doing more harm than good.