To me, Bel (and this may be only a personal distinction in use of words): If bin Ladin's cause would somehow be advanced by him opening proclaiming his responsibility, then I would say it is "cowardice" to forego that advantage for fear of his personal safety. But as best I can tell he would gain no benefit by announcing his role; for his purposes, it is tactically better for his cause to keep his exact role muddled and in question. That is, his open proclamation his role would perhaps be more emotionally satisfying to us (and perhaps to him too), but is not in the best interest of his own (warped) cause.