I have argued elsewhere (Reid 1993a) that Islam also wrought changes, more slowly, in the Southeast Asian attitude to political power, tending to encourage greater concentrations of power in certain radically reforming rulers. Change in this, as in other respects, was neither all of a piece nor gradual and imperceptible. Islamization provided the potential for radical change by introducing an external set of ideals to which radical reformers could appeal with spasmodic hope of success. Some of the most radical changes came in the sixteenth and early seventeenth centuries, because socio-economic conditions gave sustenance to such radical visionaries (Reid 1993). Later phases of traumatically rapid socio-economic change occurred around the turn of the twentieth century, and in the 1970s and 1980s, giving further fuel to what is today often called fundamentalism. The Austronesians of Southeast Asia are no more inclined than anybody else, however, to sustain such idealisms over lengthy periods.