The man threatening the status quo in one of the world's most politically entrenched regions is not the sort of person given to grandiose gestures or impassioned oratory.
Compact, neat and precise, 73-year-old former Syrian Vice President Abdul Halim Khaddam has the quiet assurance of a man who has spent three decades in one of the Middle East's most formidable power circles.
But it's the content of his statements these days that's shaking international circles.
"President Bashar al-Assad's policy is built on personal interest for him and his family," he said, referring to the current Syrian leader during an interview with ABCNEWS.com at his luxurious Paris residence.
"All the decisions he has taken on, internal and external issues, have put Syrians in a corner, and the country is in a very dangerous situation," he added. "My role now is to finish the bad situation for the Syrian people right now and get rid of the regime."
Delivered dispassionately in his Paris living room more than 18 months after his resignation, Khaddam's quiet resolve seems far removed from the intrigues of Syrian politics.
But it's a dramatic break from his former boss in the Syrian capital of Damascus. This, after all, is the seasoned statesman who signed vital decrees enabling the young, inexperienced Assad to take over the presidency after the sudden death of his father, Hafez al-Assad, in 2000.
Even more explosive are his recent public insinuations that Bashar al-Assad played a role in the assassination of former Lebanese Prime Minister Rafik Hariri.
Months after a U.N. investigator's report cited witness testimony that Assad had personally threatened Hariri before his killing, Khaddam is publicly implicating the Syrian president in the assassination.
Syria has consistently denied any involvement in Hariri's killing. But Khaddam's accusations have been the most serious blow to Assad, coming from one of his most senior officials.
Indeed Khaddam's latest salvo is just one shot -- albeit an extraordinarily powerful -- in a fusillade against the regime.
Alienated from the international community -- including former ally Saudi Arabia -- and facing mounting U.S. criticism over its alleged role in the Iraq insurgency, the once-solid Damascus regime is starting to display potentially fatal cracks.
One crucial result of Khaddam's denouncement of the Damascus regime is its impact on the Syrian opposition at home and abroad.
Given the regime's tight control of the media and its authoritarian crackdowns on the opposition inside Syria, it's difficult to conclusively assess the effects of Khaddam's falling-out inside the country.
But outside the Baathist-controlled country, there's little doubt that it has bolstered the Syrian opposition in exile.
"It certainly boosts the self-confidence of the opposition to realize the major rats are deserting the sinking ship," said Volker Perthes, director of the Berlin-based German Institute for International and Security Affairs.
"Judging from the nervous reaction by the [Syrian] regime, it shows Khaddam has touched a weak spot. And what weakens the regime, strengthens the opposition," he added.