Iraquis are split into three main groups: Sunni Kurds in the north (about 20%), Shit'ite Arabs mostly in the south (50%+), and Sunnis Arabs mostly in the center (the remaining 20-30%). The first two groups hate the third, which holds all the power. But without removing their fingers from the levers of power, the first two cannot overthrow the third.
Saddam has remained in power primarily by leading the dominant Sunni Arabs to believe that he is the only one that can keep them on top. Their future would be bleak if they ever lost dominance. In the Middle East, you don't just retire.
It's a different, permanent kind of retirement. Some think there are 30 virgins involved, but apparently the psychos in the ME are not aware that these are really big virgins named Bubba. That is why we (normal people) call this place Hell.