Moderates have been sidelined, and despite efforts to revitalize the opposition's political leadership in exile there is still no umbilical cord between the government-in-waiting and the fighters inside Syria.
The Free Syrian Army coexists with a strong Sunni jihadi element, while the regime is mobilizing "irregular" Alawite militia and Hezbollah fighters.
Syria's (largely Sunni) rebels say hundreds if not thousands of (Shia) Hezbollah fighters are now fighting for the Assad regime. Hezbollah's secretary-general, Hassan Nasrallah, said last week that his party would not stand by and watch the Assad government fall. Regional analysts believe there is a very real risk that along the poorly marked Syrian-Lebanese border, Sunni jihadists will come up against Hezbollah units, setting off a vicious war-within-a-war.
The Syrian opposition sees Iran and Hezbollah everywhere. The head of the UK-based Syrian Observatory for Human Rights, Rami Abdel-Rahman told the newspaper Asharq al-Awsat that "Iranian and Hezbollah officers are running the operations room in the battle for Homs and are controlling the army operations in the city."
He warned of "massacres against the Sunni community living in the besieged areas if the army captures these areas."
Such massacres were reported in the past week in the coastal Sunni enclaves in Baniyas and al-Bayda. The State Department said over the weekend that "regime and shabiha forces reportedly destroyed the area with mortar fire, then stormed the town and executed entire families, including women and children."
3: Al-Assad goes for broke?
After being on the defensive for months, the Syrian regime has recently launched a series of brutal counterattacks against areas controlled by rebel factions, seeking to restore precious lines of communication and reconnect Damascus with other parts of the country. In so doing, it appears Assad has relied even more on the shabiha -- loyalists with an existential stake in the regime's survival.
As veteran Middle East watcher Anthony H. Cordesman of the Center for Strategic and International Studies has put it: "The Assad regime seems ready to escalate in any way it can to either preserve power or effectively divide the country."
Among the areas where this counteroffensive has been most intense is Daraya, south of the capital, which has been reduced to ruins on the principle that "if we can't control it nor shall you." To the east of Damascus, regime forces have encircled rebels in the Gouta region, relieving the immediate threat to Damascus airport, which is at one end of the critical air bridge between Syria and Iran.
As critical as these areas around Damascus is the town of Qusayr between Homs and the Lebanese border, once home to 50,000 people. Videos uploaded in recent days show the regime pouring artillery fire into the town and conducting airstrikes from above; whole blocks have been demolished. Claims emerged Wednesday from opposition sources of new massacres around the town.
Qusayr sits astride one route to the Syrian coast and another to the Lebanese border. For the rebels, holding Qusayr is important because it's another way of strangling the regime's ability to sustain itself, and it complicates Hezbollah's access to Syria.
The signs are that al-Assad is investing heavily in trying to break the rebels' hold in key parts of south and central Syria, reversing the gains they had made in a series of hard-won victories last year.
Short of forceful foreign intervention, some military analysts argue for tying al-Assad's hands behind his back by providing the rebels with more anti-armor and anti-aircraft missiles and a communications infrastructure. More ambitiously, some say the international community should enforce what might be called a "no-move" zone, selectively picking off regime forces from the air or with missiles.
In essence, that's what NATO's mission in Libya became. But it would take considerable airpower and the use of facilities across the region to gain control of the Syrian sky. The chairman of the U.S. Joint Chiefs of Staff, Gen. Martin Dempsey, said at the end of April: "The U.S. military has the capability to defeat that system (of Syrian air defenses), but it would be a greater challenge, and would take longer and require more resources" than in Libya.
4: Chemical Weapons
For much of last year, Obama's "red line" seemed a largely hypothetical one. But as al-Assad's situation grows more desperate and control of chemical weapons stocks more difficult to guarantee, there are indications that some chemical agents have been used in limited quantities in places like Daraya. The questions are: how much, of what and by whom?
The announcement by a senior U.N. official Monday that rebels may have used sarin gas during an operation near Aleppo in March means this red line is even more difficult to discern. The U.N. commission subsequently said it "has not reached conclusive findings as to the use of chemical weapons in Syria by any parties to the conflict."
Establishing "custody" and the systematic use of such weapons is very difficult in the absence of monitors on the ground.
A U.S. State Department official on Monday would say only: "We take any reports of use of chemical weapons very seriously and we are trying to get as many facts as possible to understand what is happening."
But understanding and countering the threat are miles apart. The Pentagon estimated last year it might take 70,000 troops to secure or destroy Syria's massive stockpiles -- and the situation on the ground has deteriorated since then.
In Cordesman's view, "Any U.S. forces that tried to deal with the chemical weapons in Syria through ground raids would present the problem of getting them in, having them fight their way to an objective, taking the time to destroy chemical stocks, and then safely leaving."
5: Players and Puppets: Iraq, Turkey, Lebanon and Jordan
Syria is surrounded by neighbors with a stake in influencing the outcome of its civil war. Most -- and other more distant states such as Qatar and Saudi Arabia -- are backing their own factions as well as supporting the "government-in-waiting." Now more than ever they feel the force of that whirlpool.
Iraq's beleaguered Sunni minority is more and more in confrontation with a Shia-dominated government in Baghdad allied to Iran. The Sunni tribes of Anbar and Ramadi have historical connections with their brethren across the border and would welcome a Sunni-dominated government in Syria as a valuable counterbalance to a hostile government at home.