Western commentators typically attribute such behavior to Putin’s personal paranoia or to attempts to rekindle the nation’s wounded pride and assert Russia’s superpower status. Look a little closer, however, and Russia’s actions seem motivated more by calculated — albeit sometimes miscalculated — realpolitik than by psychological impulses.
First, strategic interests are at stake. In Tartus, Syria hosts the sole remaining Russian naval base on the Mediterranean, currently being refurbished by 600 Russian technicians after long disuse. To have to give up this Middle Eastern beachhead would be a shame, as far as the Russians are concerned.
Second, although limited, Russia has real commercial interests in Syria.