For days Syrian warplanes and artillery have been relentlessly bombing rebel-held positions on the outskirts of Damascus as they try to secure that area around the capital, Patrick J. McDonnell of The Los Angeles Times reports.
The Syrian army "has completely opened the gates of hell before all who would even consider approaching Damascus or planning to attack it," the pro-government Al Watan newspaper reported Sunday.
But rebels reportedly control stretches as close as a mile from the Damascus International Airport — leading to the cancellation of flights into Monday — and have captured a military helicopter airport and the main road leading to the airport.
Damascus Revolutionary Military Council spokesman Abu Eyaad told CNN that the opposition's main goal "is to sap the strength of the regime's air force and supplies."
The UN is now sending "all non-essential” international staff out of Syria, and BBC foreign editor Jon Williams notes that it is a "huge call. Halting aid missions outside Damascus as situation deteriorates."
Rebels have vowed that they will not stop until they topple Syrian President Bashar al-Assad's regime, and several recent developments indicate that the rebels have significant momentum in the 20-month conflict.
Rebels now have a stockpile of weapons
The opposition now have at least 40 shoulder-fired anti-aircraft missile systems from government stockpiles or elsewhere and are shooting down attack Assad's warplanes, which means they've achieved the potential to neutralize one of the critical aspects of the regime’s defense.
The rebels continue to receive U.S.-made weapons through Qatar and Saudi Arabia.
The Syrian regime has its own stockpile of chemical weapons, which have recently been moved in a way that suggest Assad is preparing to use them.
Rebels control, consolidate and constrict supply routes all over the country
Assad lost control of the northeast part of the country in the summer and recently lost critical ground along supply routes in the northern Aleppo Province as well as around Damascus. The road connecting Aleppo and Damascus is already under rebel control.
In the last month rebels have captured key oil fields in the east of the country, and the huge rebel-controlled territory along the Iraqi border is now the largest outside government control.
A lot of Syrian troops and officials have defected
Today Reuters reports that Foreign Ministry spokesman Jihad Makdissi has defected. The defection is one in a long line of high visibility departures from the upper echelons of Assad's military and government apparatus.
Thousands of regular Syrian Army soldiers defected to fight on the side of the rebels, and to make matters worse for Assad, the officer corps has also taken a serious beating. In total, 44 generals and several more lower ranking officers have fled the country for Turkey.
Assuming the Syrian Army is comparable to most modern militaries in terms of officer to troop ratios, that would put anywhere from one third to half of Assad's General Officer Corps out of commission. Historically speaking, the flight of generals is one of the surer signs of impending collapse — a stark and not so subtle reminder that not even those at the top are confident of an unfavorable outcome.
International support for the opposition has never been higher
The "Friends of Syria"– which includes the U.S., the European Union and Arab League – recently met in Tokyo to coordinate further sanctions on Assad's regime.
Turkey has asked NATO to establish Patriot missiles on its border to bolster air defenses, and U.S. Secretary of State Hillary Clinton said she expects the request to be granted.
Iran, China and Russia – the last of which has reportedly continued sending attack helicopters and weapons to Syrian forces – are still in Assad's corner.
Nevertheless, the regime will make its toughest stand yet to hold Damascus.
Experts told The New York Times that the government's defense of the capital could be the fiercest and most destructive phase yet of the 20-month conflict. Assad's best and most loyal troops (along with much of his artillery) remain at the center of the city. They'll clash with better-organized units of army defectors in southern Syria, and with Jordan's force that's been training to attack Damascus.
Emile Hokayem, an analyst based in Bahrain for the International Institute for Strategic Studies, told the Times that everyone is simply "waiting for the big battle to begin.”
SEE ALSO: How The Syrian Conflict Is Going To End
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