A commander in Iran's Revolutionary Guard Corps admits that the government in Tehran is not just offering moral and financial support to Bashar al-Assad, but has actually contributed foot soldiers to reinforce Syria's army. 

As The Guardian's Saeed Kamali Dehghan reports, Iran, like Syria's government, blames the uprising on foreign terrorists, claiming that by providing military to support to the regime it has prevented more deaths. Ismail Gha'ani, the deputy head of Iran's Quds force, said in an interview that "If the Islamic republic was not present in Syria, the massacre of people would have happened on a much larger scale."

However, if the reports are true then they have almost certainly extended the conflict beyond its natural life, as Assad's army has seen wave after wave of defections from rank-and-file troops as well as the loss of dozens of top commanders who have fled the country. It also lends credence to claims from opposition forces that kidnapped 48 Iranian citizens who the Free Syrian Army claimed where members of the Guard. Iran insisted they were just religious pilgrims and has demanded their release. 

As Iran has become increasingly isolated from other countries in the Middle East, it sees Syria — and by extension, Hezbollah in neighboring Lebanon — as one of its last spheres of influence in the region. That's why its sending in its own army to fight while attacking the United States and other nations for trying to intervene in Syria's affairs.