A Berserk Psychopath?

Could the Norway mass murderer, who evidently committed the worst single massacre by an individual in history possibly be sane? I would contend yes absolutely, that he acted coolly, methodically, with malice of forethought, and coldly executed a meticulously hatched plan. Like Charles Whitman, the University of Texas shooter, or James Huberty, the McDonald's murderer from San Ysidro, California, this creature has secured for himself an infamy, a vile notoriety where all decent people will curse his name.