Iran helped Syria grow its WMD stockpiles

Washington Post:

Syria has expanded its chemical weapons arsenal in recent years with help from Iran and by using front organizations to buy sophisticated equipment it claimed was for civilian programs, according to documents and interviews. 

The buildup has taken place despite attempts by the United States and other Western countries to block the sale of precursor chemicals and so-called dual-use technology to Damascus, according to the documents. 

As recently as 2010, documents show that the European Union provided $14.6 million in technical assistance and equipment, some intended for chemical plants, in a deal with the Syrian Ministry of Industry. Diplomats and arms experts have identified the ministry as a front for the country’s chemical weapons program. 

Recognizing the potential for Syria to divert equipment to the weapons program, the E.U. stipulated that it be allowed to conduct spot checks on how it was used. But the inspections were halted in May 2011 when the organization imposed sanctions on Syria after the crackdown on opposition groups.

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Arms experts say Syria has pursued a two-pronged strategy to build and grow its chemical weapons stockpile: overt assistance and procurement of chemical precursors and expertise from Iran, coupled with the acquisition of equipment and chemicals from seemingly unwitting businesses in other countries, in many cases through a network of front organizations.
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There is much more.

I suspect they also got some WMD from Iraq as the UN and US put pressure on Saddam over his own programs to develop WMD.   But Syria already had an active program at that time and it appears it has been trying to enhance and build on that program in recent years. With its army enfeebled and over stretched by its current civil war, Syria is likely to use its WMD if outside forces attempt to shape the outcome of the civil war too soon.