Just like inexperienced predators in the wild must learn to hunt by watching their parents, so in Iraq did Saddam Hussein's sons learn to prey on their own by watching and copying their tyrannical father.

"Saddam, to prepare his sons for ruling Iraq, exposed them at an early age to executions and to torture. It's his mentality that they should be toughened up, that they should show no mercy," said Ali Sharif, president of the Iraqi National Congress, an opposition group. "The two sons of Saddam Hussein really are incredibly evil."

The brothers Hussein — Odai and Qusay — learned their lessons well. They went on to main and kill thousands of their own countrymen, according to Sharif.

"They take pleasure in torture and murder, just because that's their nature," he said.

Con Coughlin's new book, Saddam: King of Terror, also paints a sinister portrait of Saddam's sons.

"Both boys are classic examples of spoiled brats," he said. "Odai actually went to school with a gun in his pocket, and would terrorize the other children. If he got into fights with other kids, he would have the bodyguards take the kids out, and they'd be tortured or something like that. This has been going on since a very young age."

A friend of Iraqi exile Entifadh Qanbar, Washington director for the Iraqi National Congress, fell victim to Odai's homicidal madness after he refused to allow Odai to sleep with his fiancée.

"[Odai] is crazy," Entifadh said. "Even he admits it. He cannot control his rage. He has amazing rage. For any little reason, he could kill a person."

In the end, Odai terrorized the woman and had her husband-to-be murdered.

"Odai somehow went to the woman, without [my friend's] knowledge and raped her as a punishment for not obeying his orders," Entifadh said.

And that wasn't an isolated incident.

"There are many stories of Odai raping women and killing the boyfriends of girlfriends who protest when Odai makes advances," Coughlin said. "Odai was his father's pride. Unfortunately, Odai became somewhat of a psychopath."

According to Newsweek editor Mike Hirsch, not even Saddam could tolerate Odai's uncontrollable temper.

"Odai appears to have gone somewhat over the top, even for Saddam Hussein," he said. "[Saddam] has punished him apparently by removing any important jobs from his portfolio and giving him these rather marginal-type jobs: head of the Olympic committee, a newspaper to run, really no important levels of power."

Saddam's eldest son couldn't manage to oversee those responsibilities without acting out his masochistic tendencies. Under his direction, the Olympic committee taught everything but good sportsmanship.

"The Iraqi Olympic organization developed a reputation for great brutality in the basement of the headquarters of this facility in Baghdad where there's a prison complex," Coughlin said. "I've interviewed people in my book who have been tortured at this complex. Odai himself would come down and supervise the torture."

Not even a brush with death would change Odai's ways. In 1996, he survived an assassination attempt and several gunshot wounds. He has used a wheelchair ever since. Most analysts believe that he was crippled from the waist down, according to Hirsch.

"He's had several of his friends, had their legs broken and forced to walk around as well on crutches and with walking sticks because he can't bear to see them walking around while he needs to be in a wheelchair," Sharif said.

Although not as demonstrably unstable as his older brother, Qusay is considered just as lethal.

"Since the assassination attempt in 1996, Qusay has been the heir apparent. It is Qusay who would take over the control of the regime if anything were to happen to Saddam," Coughlin said.

Like his father before him, Qusay is responsible for the murders of tens of thousands of people, according to the Iraqi National Congress.

"Qusay is complicated. Qusay is very calm, very quiet, very polite. He makes a lot of sense when you talk to him... but he's a notorious killer," Entifadh said.

And with Odai out of serious involvement with his father's regime, Qusay has stepped in to fill the vacuum.

"From the mid-1990s, he's been in charge of the special security organization which has responsibility for protecting Saddam," Coughlin said.

That includes hiding dad's dirty little secrets.

"All the key materials — chemical and biological — and the details of the nuclear research program has been concealed effectively by Qusay," Coughlin said.

Now the butcher's brood has instructed their thugs to fight coalition forces using tainted tactics.

"The guerillas harassing U.S. and British troops are Odai's troops. It would be of course exactly their M.O. not to follow the rules of the Geneva Convention," Hirsch said. "I think what you'll see [in the decisive battle of Baghdad] is Qusay's men, Republican Guards. It will be his tactics at play here."

Like their ruthless rulers, these troops fight dirty, posing as surrendering soldiers and firing on our GIs or disguising themselves as U.S. and British troops to slaughter surrendering Iraqis.

"[These are] hit-and-run attacks, soldiers dressing up as women, using civilians as human shields," Coughlin said. "This is textbook Saddam, and Qusay would have been responsible for putting all these measures into place."

Blood brothers to the core, these rotten apples didn't fall far from the tree.

"They grew up, soaked in blood in this particular butcher shop," Hirsch said. "It was probably pre-ordained that they would turn out to be monsters like their father."