Irrelevant if Assad stays in power or the rebels take control, what’s important to know about Syria is that an attack on Syria is an attack on Iran and a threat to the Shanghai Cooperation Organization (SCO) - a mutual security organization founded in 2001, which “includes not only the two giants Russia and China, but also the energy-rich Central Asian states Kyrgyzstan, Uzbekistan, Kazakhstan and Tajikistan.”
In 2006 Syria signed a defense agreement with Iran. With this agreement Iran "considers Syria's security its own security," and its defense capabilities to be those of Syria. This means that an attack on Syria is an attack on Iran, and Iran is a much more formidable foe than Syria. Not because of Iran’s military capabilities but because of its diplomatic ties to the regional countries.
Not only has Iran signed a declaration with Caspian Sea leaders in which all parties have agreed “to reinforce peace, stability, economic development, and good neighborliness in the region,” Iran is also an observer state in the SCO.
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If the United States attacks Syria, which it has threatened to do, it will force it into a military confrontation with Iran. If this occurs, it is very unlikely that the SCO, especially the two most influential members Russia and energy strapped China, will stand idly by.
Direct Western intervention in Syria or a war with Iran will be catastrophes on their own, but they could also trigger a confrontation between NATO and the SCO. Not a good scenario any way you look at it.
August 27, 2013: American forces ready to strike Syria if ordered, U.S. defence secretary says July 12, 2013: Who is the US arming in Syria? President Assad rubs his hands at news of rebel split June 16, 2013: Russia, US heading for confrontation over Syria - "Moscow has announced the dispatch to Syria of two warships carrying 600 Russian marines. They were being sent to Syria, "to protect the Russian citizens there", said an official statement." June 16, 2013: Iran to send 4,000 troops to aid President Assad forces in Syria June 13, 2013: United States officially enters the war in Syria - "The president has made a decision about providing more support to the opposition that will involve providing direct support to the [Supreme Military Council]. That includes military support." June 5, 2013: As U.S. Deploys Patriot Missiles and F-16s to Jordan, Could Syrian Conflict Engulf the Middle East? May 28, 2013: Russia Says End of European Arms Embargo on Syria Harms Hopes for Talks