Holocaust deniers

I have always wondered: the people who deny the Holocaust ever happened hold the kind of views held by, for example, Ahmedinejad, Nick Griffin, David Irving, Hizb ut-Tahrir, former leader of Reading Borough Council David Sutton, you know the kind of thing. But you'd think, wouldn't you, that people who hold those views would be pleased about the Holocaust. In the words of the immortal Rolf Harris version of "Stairway to Heaven" "Ooooh, it makes me wonder, what about you blokes?"