"If you are not confused, you don't understand the situation." So said a Belfast graffito of the late 1970s--a hauntingly accurate comment on the political violence that has raged in Northern Ireland for generations. The causes of that violence are complex, and all but impenetrable to it has something to do with religion, something to do with economics, something to do with politics, and very much to do with memory and history, along with the local penchant for remembering wrongs and rights for years and years after the actual events. New York-based journalist and historian Jack Holland, whose ancestors are Northern Irish, Catholic and Protestant both, does much to clarify the confusion with Hope Against History . He writes of the Troubles over the last 30-odd years, a time when militant forces favoring continued union with Great Britain battled those seeking union with the Republic, a battle that quickly degenerated into terrorist warfare that killed far more innocents than combatants