The Iranian mercenaries have made all the difference for the government forces. Iran has been recruiting Shia gunmen in Iraq, Lebanon and elsewhere for the last few months and providing transportation to Syria, weapons when they arrive, and regular pay. The Iranians also encourage Shia men from around the world to come join the fight against Sunni radicalism (which often results in terror attacks on Shia civilians). More than 10,000 of these Iranian mercenaries have given the Assad forces armed fanatics to match the Islamic radicals among the rebels who have often been a key element on the battlefield. Iranian cash also props up the ragged economy in parts of the country the Assad government still controls. The reinforced and reinvigorated Assad forces have recently made gains in the cities of Damascus, Homs, and Aleppo. Rebel victory is no longer imminent.
The Iranian mercenaries are not under any centralized control, although Iran tries to exercise some control via threats to hold back on payments and supplies for groups that appear to be going rogue or simply not cooperating. The civil war, like most civil wars, has resulted in a lot of armed groups going freelance and operating like bandits and organized looters. Even the Syrian Army has allowed its troops to loot in pro-rebel villages and neighborhoods. It’s good for morale.
The rebels basically live off loot. Much of their ammo and many of their weapons were taken from Syrian army troops and bases. This has made Iranian ammo shipments (from Iran via Iraq) vital. Several hundred tons of ammunition arrives each week. The Syrian Army has lost a lot of their pre-war ammo stocks (either through use, destruction, or capture). The army has put a priority on protecting high-tech weapons (lethal chemicals, ballistic missiles, guided missiles, anti-aircraft systems, and warplanes), which has led to the abandonment of warehouses full of small arms ammo, grenades, mortar shells, and the like. The army also continues to fire SCUD type missiles at rebel held towns and neighborhoods, rather than risk rebels capturing these missiles (which would likely be blown up rather than abandoned intact).
The neighbors are strengthening border security because of the increased smuggling and general criminal activity coming out of Syria. The millions of Syrian refugees in Turkish, Lebanese, and Jordanian camps provide bases for rebel and criminal groups alike. The tighter border controls has led to more gun battles with armed groups coming in and more delays for refugees coming out and goods using the main roads (which are the monitored crossings). The refugees cause economic and social problems for the locals as the foreigners are willing to work cheaper and have increased crime wherever they are. About 15 percent of Syrians have fled their homeland and nearly half as many have had to flee their homes for another refuge inside Syria. All this is playing a role in Europeans becoming more interested in defeating the Assads and making it possible for the refugees to go home. Many of the Syrian refugees are trying to move on to Europe, either legally or otherwise. The Europeans know from past experience that the only way to stop this is to bring peace at the source.
Rebel leaders from umbrella groups like the FSA (Free Syrian Army) and the SNC (Syrian National Council) have been meeting with UN representatives and let it be known that they were willing to negotiate with the Syrian government if the Assad family gave up power. The rebels also want Russia to halt its support of the Assads and for something to be done about Iranian and Iraqi support for the Assads. The problem here is that Russia (and China), Iran, and Iraq all back the Assads and know that any other government in Syria would be hostile to the Assads (and Assad allies) and their track record of cruelty and corruption.
Turkey is now moving towards more active support for the moderate rebels. That means FSA and SNC but not Islamic terror groups like the new (formed this year) Syrian Jabhat al Nusra (JN), the decade old Islamic State in Iraq (ISI), and smaller radical groups. Turkey is worried about the radicals among the rebels becoming more active allies of Islamic radical groups already in Turkey (and largely kept under control). The Turks are offering the Syrian Kurds (who have been at war with Islamic rebels in Syria) aid and inclusion in the recent peace deal with Turkish Kurdish rebels (the PKK). The Turks are trying to get the Syrian Kurds into the SNC as well.
There is growing anti-Assad and anti-Hezbollah violence in Lebanon. This takes the form of ambushes and assassinations, most of them directed at Assad supporters (who are a minority in Lebanon). Hezbollah is fighting back using its own fighters and those it has in the Lebanese police and armed forces. Some army battalions are almost entirely Hezbollah men and are in fact under the control of Hezbollah and the army. While these troops normally follow army orders, if the army ever tried to go after Hezbollah these battalions would switch sides. Many Lebanese are unhappy with the Hezbollah intervention in Syria and have become less reluctant to trigger another Lebanese civil war to shut down Hezbollah and its seemingly insatiable lust for power. The Arab world in general is increasingly hostile towards Hezbollah for so blatantly taking sides in the Arab struggle against Iranian domination of the Persian Gulf (which the Arabs prefer to call the Arabian Gulf, so you see where all that is going).
Hezbollah problems extend beyond the Arab world. On July 16th the EU (European Union) finally agreed to declare Hezbollah a terrorist organization. For a long time many EU members were convinced that Israel was really at fault here and that the Hezbollah members involved in terrorism were exceptions. So the EU refused to label Hezbollah a terrorist organization and limit their fund raising and recruiting inside Europe. But since the recent Hezbollah intervention in the Syrian civil war, the growing mountain of evidence became too difficult to deny. The Gulf Arab states that support the Syrian rebels have also warned Hezbollah that if they do not withdraw their gunmen from Syria, Hezbollah will be added to the Arab list of terrorist organizations and Hezbollah will no longer be able to operate openly in most of the Arab world. This would hurt Hezbollah big time. Hezbollah needs the Iranian support to survive and is now in a position where it will take some major losses no matter what it does. So will Iran, which has long considered Hezbollah ones of its major achievements. The EU ban (only on the “military wing” of Hezbollah) makes it more difficult, but not impossible, to raise money and recruit in Europe.
The U.S. has finally begun shipping the promised military supplies to the rebels. Political disputes in the U.S. has delayed following through on month old pledges to provide aid. Currently, the U.S. is testing the reliability of rebels supply lines and the independent smuggler groups used to get goods from Turkey and Jordan to rebel units inside Syria. The U.S. is sending non-military items in via these channels and using agents (usually trusted local hires) on the other side to keep score.
July 29, 2013: Iraqi Sunni Islamic radicals kidnapped an Italian priest who had been active in the Syrian Christian community and sought to establish better relations between different religious and ethnic groups in Syria. The priest also criticized the Assad government for exploiting ethnic and religious differences. The priest apparently angered the Iraqi Islamic terrorists by criticizing that groups attacks on Syrian Kurds. Kidnapping has become frequent, usually as a way to coerce a group (family, clan, combat unit) to do something. If that doesn’t work the hostage is often killed and the body dumped somewhere. This has resulted in thousands of missing persons that may never be found.
July 26, 2013: For the fifth time this year Israel attacked a target in Syria. This time it was high-tech weapons stored at an army base north of the Israeli border (near Quneitra). The attack was carried out by warplanes and, as in the previous attacks, was part of an effort to prevent Syrian weapons from being moved to Hezbollah bases in Lebanon.