How Putin's Russia props up Assad's military

For the last 60 years Russia has been Syria's main weapons supplier, selling it everything from fighter jets to tanks and a formidable array of air defence systems. Syria's current arsenal would present significant problems to any attacking western attacking force. Its air defence missiles, in particular, would make establishing a no-fly zone extremely tricky, and any manned air attack would probably result in western casualties. This is certainly not Libya.

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