It does not have enough popular backing to sweep away the Assad regime. It does not have enough military clout to challenge the standing army that is still loyal to the government to a great extent. It does not have enough international support to act as a shadow government. Even Israel, the archenemy of Syria, wants the Assad clan to stay in power because it is predictable and would not dare to confront the Israeli military and attempt to recover lost territories like the Golan Heights.
But more than anything else, the Syrian opposition does not inspire enough confidence that it can hold the country together and establish a pro-Western government. No one wants a sectarian opposition that could incite inter-faith conflict and that would be likely to clash with the West.
People are worried that a sectarian post-Assad government will cause sectarian strife as occurred in Lebanon, tearing the country asunder two decades ago. Furthermore, the secular nature of the present regime is a guarantee for the maintenance of religious pluralism in the country as the West dreads religious fundamentalism along the shores of the Mediterranean Sea. When all of these factors are put together, the Assad government looks like it could survive for some time to come.
Getting a sense of this reality, the incumbent government wants to crush the opposition in the shortest time possible in order to ease internal and external pressures brought to bear on it. That is why it is trying to beef up its military capabilities against both internal and external threats.
In this quest the Syrian government is mainly relying on Russia and Iran, which have geopolitical reasons for maintaining the Assad regime. The US hegemony in the Middle East is challenged via Damascus, while Russia can retain its old naval base in Tartus, which gives it an edge in the eastern Mediterranean region as it did for the Soviet Union.
Just like Russia, Iran is also an arms supplier for Syria, sharing strategic interests with it. Both Russia and Iran want to keep Syria as a key actor in the Middle East to prevent a Pax Americana from shaping the region. Additionally, a second (sub-state) actor, namely Hezbollah, is being groomed to challenge Western (including Israeli) influence in the region. That is why critical military supplies are handed over to Syria. Some of these eventually find their way to Hezbollah in Lebanon.
These weapons systems may be rather disturbing when used against Israel during an air strike by this country on Iran’s nuclear facilities. But this is not all. In several articles in Haaretz, it has been reported that surface-to-air batteries and effective anti-ship cruise missiles have been given to Syria by Russia. These are SA-17 surface-to-air missiles and powerful SA-24 Grinch shoulder-launched anti-aircraft missiles that can bring down aircraft flying at an altitude of 3,000 meters. Several hundred (nearly 500) of these deadly weapons were in the hands of the Libyan army and mysteriously disappeared in the civil war last year. It is believed that they found their way to Iran first, which passed some of them to the Syrian army and Hezbollah in Lebanon.
Russian-made Yakhont SS-N-26 missiles, which are believed to be in Syrian hands, have a range of 250 kilometers. They are fast and carry large payloads of explosives to ranges of 300 kilometers to sink even large warships. Such missiles are reported to have made their way into Syria, beefing up its military power against both insurgents and possible interveners in favor of the opposition.
It seems the internal strife in Syria will persist for some time to come and will only be extinguished with blood, given the inertia of the international community and the disunity and entropy of the internal opposition. Would this mean the strengthening of the regime? Hardly; it has to rely on more naked force to sustain itself, paving the way for its eventual demise.