A stirring, comprehensive life of the great Irish patriot. ``If you think you understand what's going on, you're just confused,'' says a graffito current in Belfast. The same is true of Irish history, a sprawling mess of tangled loyalties and shifting allegiances. The life of Michael Collins (18901922) exemplifies the tortured, bloody course of modern Irish history. A kindhearted and warm man who in his heyday cheerfully ordered the assassination of political and military opponents, Collins rose to international prominence as a leader of the Irish independence movement. He had first emerged as a leader during the Easter uprising of 1916, in which hundreds of combatants and civilians died, and which Collins later rued as an enterprise ``that was bungled terribly, costing many a good life.'' Mackay (Burns: A Biography of Robert Burns, 1993) carefully describes Collins's contributions to the Irish armed resistance movement against British rule, first as a guerrilla, and later as commanding general of the national army. Mackay is also good, for the most part, in recounting and analyzing the complex negotiations with England that led to the founding of the Irish Free State after a costly, vicious civil war in which Collins fell victim to a sniper's bullet. Collins's story cannot be told independently of that of his principal opponent, Eamon de Valera, who remarked after Collins's death, ``In the fullness of time history will record the greatness of Collins and it will be recorded at my expense.'' That much is true, but Mackay does not satisfactorily explore de Valera's character and motivations, and he remains a shadowy and somewhat sinister force. Neither does Mackay deal sufficiently with the charge of other historians that de Valera ordered Collins's assassination. He concludes, probably correctly, that the ambush in which Collins died was not intended specifically for him. Despite minor shortcomings, this is the best life of Collins now available, published just in time to coincide with Neil Jordan's film Michael Collins, with Liam Neeson in the lead role.