There are signs of significant rifts among Syria's foreign and domestic militias trying to overthrow Assad.
This is particularly the case with the 2 main Islamic groups: On the one hand there is the "Jabhat al-Nusra" militia (hereafter referred to as "Nusra') who are Salafist jihadists backed by Saudi and Qatari funds and political support, and closely linked to Al Qaeda and the Taleban.
Nusra fighters are among the fiercest and regularly use suicide bombings as standard operating procedure. A large part of this force is foreign, and includes mercenaries for hire from previous wars in Afghanistan, Iraq and Libya.
They are highly effective fighters, and constitute one of the most important "rebel' factions. Information on their numbers is scant.
However, this group has no other aim than to grab power for the sake of establishing a fundamentalist Salafist state.
Their level of intolerance for any form of pluralism is demonstrated by their atrocities across the previously mentioned countries' wars. They are extremely dangerous to any Syrian who is not a Salafist, and in the main they tend to come from Saudi Arabia.
The irony of having non-Syrian mercenaries who are dedicated to the establishment of a pan-Islamic Caliphate acting as the "lead force' in "fighting for democracy and freedom' in "Syria' has yet to be appreciated in full by various observers.
The other major Islamic group of fighters in Syria are the "Al-Farouq Brigades" that are more Syrian in character, and backed up by the Muslim Brotherhood, closely aligned with Egypt. They are said to have emerged from the city of Homs, which has been a hotbed of opposition to the Assad family for decades -- similar to Ben Ghazi's case against Qaddafi in Libya.
Not surprisingly, the first defectors from the Syrian army (such as Lt. Tlass) came from Homs. The numbers of their fighters are likely to be substantial, but unknown. Their funding also comes from Saudi and Qatari sources, but also the West.
The Al Farouq Brigades are said to be more "moderate' than the Salafist Nusra group. However, it is reported that 90% of Christians in the city of Homs have already left following the takeover of the city by the Farouq brigades.
Signs of a rift between the two main Islamic fighter groups emerged on 9 January 2013 when the leader of the Farouq Brigade's northern command was shot dead on the Syria-Turkey border. This killing was apparently due to his alleged involvement in the murder of a Nusra commander by the name of Firas al-Absi in September 2012.
Later again in March 2013 a firefight apparently took place in the northeast between the two groups over the detention of some Al Farouq fighters by the Nusra salfists in the area. Al Farouq's commander was shot in the incident, which reportedly took place near Tell Abiad.
These incidents reflect a fundamental rift between these two most effective forces on the ground. As the fighting rages on, and the more these groups believe themselves to be close to "victory', the more fierce will become their hostilities toward each other.
The other factions, loosely referred to as the "Free Syrian Army', which are said to have more secular leanings as compared to the 2 Islamic militias described above, have already acknowledged that a war with the Salafists is inevitable "once Assad falls'.
Signs are, that all these militias could well be at war with each other far earlier than that.