(CNN) -- On June 13, 2009, hundreds of thousands took to the streets in the largest demonstrations seen in Tehran since the Iranian revolution of 1979. They were protesting what many observers said was a rigged presidential election. The regime answered with brutal repression. Security forces admitted 2,000 arrests and some 20 killings. Families of the protesters insisted that the true number of the killed was hundreds more. Through the crisis, President Barack Obama mostly held his tongue. On June 15, he disavowed any intention by the United States to favor one side or the other. He assured Americans that the Iranian government had promised him "that they are going to look into irregularities that have taken place." Only on June 23, after 10 days of arrests, beatings, and killings, did Obama harden his tone.
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David Frum: Time after time, President Barack Obama has ducked foreign policy challenges
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He says the President declined to be forceful on Iran, Syria, Ukraine, Venezuela
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Frum: Is Obama projecting U.S. weakness? And is that provoking others to act?
"The reporting we have seen from media sources regarding alleged chemical weapons incidents in Syria has not been consistent with what we believe to be true about the @placeholder chemical weapons program."