By Mick Krever, CNN
(CNN) - Manaf Tlass was once one of Bashar al-Assad's closest friends.
"He is humble. He loves people," Tlass said when describing the Syrian leader. "But he has changed. The crisis has changed him."
Before he defected this July, Tlass was the very image of an Assad regime insider.
His father is a former defense minister.
Manaf Tlass was a brigadier general in Syria's Republican Guard. And, of course, he was a close friend of Assad's.
But Tlass became disgusted with the regime's brutal crackdown - and he learned about it in the exact same way the rest of the world has: by watching amateur video posted to YouTube.
"I remember very well how I defected," Tlass told CNN's Christiane Amanpour on Thursday. "I remember that video that I saw when they stepped on the head of a Syrian citizen in Baniyas," a city on Syria's Western coast.
"I started to feel the feelings of a citizen."
Tlass said he went to Assad and told him that the perpetrator should be punished. When Assad refused to react, Tlass knew that was it.
"Ever since then I can no longer be a friend of Bashar's," Tlass said.
"I tried to tell him that he had to give up something for the people," Tlass said of his last conversations with Assad. "That there is a true uprising and that he must go along with it. There is an Arab Spring all around us. You should be part of it and democratize the country. He refused."
"The old guard around him lulled him into handling the crisis this way."
But the falling out with Assad came early - four months after the conflict began. The last time the two spoke, Tlass says, was June 2011. It would take him more than another year to defect.
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How did he survive?
Tlass was a dissident within the regime, but he was still a true member of the inner circle. His fellow insiders told him that if he kept quiet and avoided Assad, he would be safe.
"I stayed in my office and refused to engage in any meeting or any conversation with any of them," Tlass said.
Tlass stayed silent and survived like this through many months, and many more killed.
"But then I realized that the violence was becoming unbearable and I could no longer take it," Tlass said. "My military conscience could not take that constant killing of innocent civilians."
Tlass, unlike much of the military and regime leadership, is Sunni - Assad and most of his allies are Alawite, a small Shia sect.
Nonetheless, Tlass said it is not allegiance to Assad that is preventing more Alawites from defecting. Rather, it is fear and the sense that the Sunni-majority rebels do not have a clear vision.
"Alawites are being told that the Islamists are taking over - they were considered infidels by the Islamists and that's what scares them," Tlass said. "But when there is a project for Syria that can, which can include all parties, the Alawites will defect."
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As the world continues to hem and haw on what to do about the civil war in Syria, Tlass was unequivocal about what he thought should be done - or not be done.
"I don't believe there should be any foreign intervention in Syria," the former general said.
Western powers have often cited the strength of the Syrian military as a reason for their reluctance to intervene, a point that Tlass - a former member of the military - said was simply not true.
"It will not be a danger," Tlass said almost inaudibly. "But we don't want to repeat the Iraqi experience or the Afghani experience or the Libyan experience. We want the Syrian people to liberate themselves by themselves."
That is not to say that Tlass believes the world should let Syria fester. Indeed, it is lack of "political will," as he put it, that is keeping his former friend in power.
"Everything will be different once he realizes that the international community has truly decided it's time to step down," Tlass said. "He will step down. I am certain of that."
CNN is not identifying where Tlass lives because of security concerns.
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