Renewed international efforts to reign in Iran's atomic program have shrouded another unresolved Middle East nuclear challenger, Syria. The International Atomic Energy Agency's failure to get Damascus to reveal the history of its secret nuclear reactor and related elements raise troubling questions not simply about the Assad regime's nuclear intentions but, more fundamentally, about the ability of the IAEA to act as an effective watchdog. Unless Syria provides a full accounting, its successful stonewalling will only serve further to undermine international efforts to curb proliferation. International awareness that Syria poses a nuclear threat emerged only in September 2007 when it is believed that Israeli aircraft destroyed the nuclear plant under construction in the country's remote northeast desert. The attack generated a surprisingly muted response from Damascus and Jerusalem, but in Vienna, the IAEA condemned the strike arguing that Israel should have informed the agency about Syria's installation. Israel's unwillingness reflected a common and growing uneasiness that the IAEA has become a hollow instrument to ferret out nuclear cheaters or reverse them once revealed. The result - Jerusalem, unwilling to risk international dithering, allegedly took matters into its own hands. THE SEPTEMBER 2009 meetings of the agency's 35 nation Board of Governors and the General Conference - the annual conclave of the IAEA's entire membership - sustained growing apprehensions about Middle East nuclear proliferation but focused on Israel to abandon its program. The General Conference only gently rapped the knuckles of Syria and Iran, calling on both "to cooperate fully with the IAEA within the framework of their respective obligations." The statement reflected a "coaxing" strategy - repeated requests that nuclear transgressors provide transparency and eliminate contraband - that has become the agency's trademark to constrain violators. The approach builds on the hope that calibrated calls for openness can prompt transgressors to feel more comfortable with revelation. However, too often the response is otherwise. Violators throw a few bones followed by agency demands for more. The dance repeats but never comes to a satisfactory non-proliferation conclusion. The Iran case illustrates. Coaxing discouraged the revolutionary regime from bolting the non-proliferation treaty while tethering it to safeguards on declared nuclear sites. Coaxing also generated IAEA inspector access to sites otherwise unavailable for review, but not "comprehensive" nuclear transparency. But the policy also allowed Teheran to buy time to build a nuclear weapons breakout capacity. Evidently, Syria has learned much from the Iranian experience as it denies agency requests for a full explanation of its nuclear enterprise. The behavior reveals why coaxing that buys time wastes time to promote accountability. Syria, which became an NPT party in 1968, applied safeguards to a small research reactor in Damascus in 1992. The agreement required Syria to inform the IAEA about any planned nuclear installations. The alleged Israeli strike clearly spoke to the Assad regime's failure to do so. In a time line provided by Washington eight months later, officials traced the origins of the Dair Alzour reactor to a collaborative North Korean undertaking that broke ground in 2001. Israeli operatives confirmed the facility's weapons potential prior to the assault, although there remains the mystery of how Damascus intended to extract weapons usable plutonium absent a chemical extraction plant. Following the attack, the IAEA attempted to get Syria to clarify the plant's purpose. Ten months would pass before Damascus allowed inspectors access to the site. Syria used the interim to demolish the installation's skeleton. It then buried its foundation, plowed over the ground and built a structure over the remains. It removed debris to an undisclosed location. Despite the cover-up, inspectors found uranium particles in soil samples. Syria unsatisfactorily explained that the residue came from Israeli munitions that destroyed the plant. IN FOUR reports published by the agency since 2007, Director-General Mohammed ElBaradei repeatedly called upon an "uncooperative" Damascus to reveal the facility's function, the uranium residue and the location of debris carted away. He also requested access to three additional suspect sites. Syria stonewalled. Damascus' repeated resistance to transparency naturally raises questions about what the Assad regime is hiding. But Syria's behavior also begs a response to an equally fundamental matter: How ought the international community deal with current and future violators? Evidently coaxing does not work. Transgressors see coaxing as IAEA impotence. Change requires the agency and the Security Council to replace the practice with meaningful "benchmarks" enforced by with "time certain" sanctions that nuclear violators cannot ignore. In the months to come the IAEA will have an opportunity to strengthen its policing function, with a new director-general in December followed in May 2010 with the important NPT Review Conference that convenes every five years. The meeting offers an opportunity for attendees to press the Security Council to authorize the IAEA to be more assertive with nuclear violators. The practice is long overdue. The writer served as a State Department policy analyst during the George H.W. Bush administration and as a consultant to the US Senate, Rand, Nuclear Control Institute, Henry Stimson Center, Global Green and Committee to Bridge the Gap.