The Syrian Government first agreed to allow an international inspection team to enter the country, and requested that it conduct an investigation in Aleppo. But when the UN asked to extend its mission to the whole of Syrian territory, the Syrian Government flatly refused.

The lingering question

Although the Syrian opposition has gained some combat success during the past two years of fighting, they still cannot compete with the government. The only force capable of defeating the Syrian Government is the United States. The U.S. side warned previously that if the Syrian Government crosses the "red line" of using chemical weapons, then militarily intervention would be considered. The announcement gave the Syrian opposition a clear sign that President Bashar al-Assad, if he made such a misstep, could be faced with a U.S. military strike.

Undoubtedly, the Syrian opposition hopes the Syrian Government would make such a mistake. In order to provoke the West into conducting military attacks against al-Assad, the opposition may have staged incidents and cast the blame on the government. Two slaughters in 2012 were already proven not to have been perpetrated by government forces. And investigations later confirmed that the Syrian Government was not involved in the bomb attack against Turkey.

Al-Assad is aware that using chemical weapons would lead to nothing but military intervention from the West. To someone in his position, facing the twin pressures of internal and external opposition, he is unlikely to cross that red line. The accusations against al-Assad by the Syrian opposition and the United States are therefore very suspicious.

The al-Assad administration's chemical weapons have been the focus of Europe and the United States since the Syrian civil war broke out. According to U.S. intelligence, Syria possesses the biggest chemical weapons cache in the Middle East. The total 500-ton chemical weapon storage includes Sarin nerve poison, mustard gas and cyanide. Syria has at least five chemical weapons plants and 25 secret weapon depots throughout the country, making it difficult to locate or track the weapons.

The Syrian Government has never denied its possession of chemical weapons. On July 23, 2012, Syria's Foreign Ministry warned that if Syria was attacked by foreign forces, it would launch chemical weapons. But it stressed that the government would never use chemical weapons on civilians. As of yet, the government has insisted that it has not employed the use of such weapons.

Syria has not yet signed the Chemical Weapons Convention banning their use in warfare. The country's chemical weapons could either be one of the al-Assad administration's last trump cards, or the ultimate trigger for outside intervention.

Fearing an unjust UN investigation result, the Syrian Government has officially expressed its mistrust of UN investigators from Britain and the United States and instead offered to allow inspectors from Russia.

Some hawkish U.S. lawmakers have urged President Obama to take action on Syria as soon as possible. On April 23, Obama warned Syria that if government forces were to use chemical weapons, then the game would change. He also said that the United States would not rush into involvement in the Syrian conflict without more solid evidence.

However, it is clear that the red line is drawn only on the side of the Syrian Government. The rule may not apply at all to the opposition. Such a blatant double standard is disturbing to the international community. The hypothetical use of chemical weapons could possibly lead to foreign military intervention in Syria. Whether or not the Syrian Government has used chemical weapons, the risk of outside intervention remains strong.

The author is a research fellow with the Institute of West Asian and African Studies at the Chinese Academy of Social Sciences

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