There are alot of people with agendas either claiming that all Arabic speaking Christians are the non-Arab inhabitants of the middle east who were Arabized by Muslim Arabs, or the reverse, that all Arabic speaking Christians are Arabs and calling Copts and Syriacs as seperate from Arabs is an evil colonialist ploy to divide the Arabs.
The truth is, that both communities exist. There are real ethnic Arab Christians, and Arabic speaking Copts and Syriacs. The Ghassanids were ethnic Arab (Greek) Orthodox Christians and claimed ancestry from Yemen (which is seen as the cradle of Arab civilization). They settled in the Levant as allies of the Byzantines, and many modern Arab Christians are descended from them in Syria, Jordan, Palestine, etc.. These Arab Christians follow the mainstream Greek Orthodox Church.
Arab Christians like Michel Aflaq played a leading role in Arab Nationalism and founding Arab nationalist parties like Baath. ANMag | The New Wonders of the World ? Part III of III
Then there are the non-Arab Christians, the Syriac speakers (in Iraq, parts of Syria, and the Maronites in Lebanon) and the Copts in Egypt. Some of them, like the Copts and Maronites, have been Arabized and speak Arabic as their native language while retaining Syriac and Coptic for liturgical purposes, while modern Assyrians still speak neo-Aramaic as their mother tongue. These "Arabized" Christians follow oriental orthodox churches.
Some of them identify as Arab and some don't. You will get some Copts and Maronites who say they are Arab and others who say they are Egyptians or Phonecians, it depends on who you are talking to. Some of the Syriac Christians in Syria aren't fans of the Baath party and the Arabization policies it used to carry out.
There seems to be a political divide in Syria between the different Christian communities. Most of the Arab Christians support Assad and the Baath Party, while alot of the Syriac Christians banded together in an anti-Assad political and military organizations, seperate from both Assad and the FSA. Syriac Union Party (Syria) - Wikipedia, the free encyclopedia
[ame=http://en.wikipedia.org/wiki/Sutoro]Sutoro - Wikipedia, the free encyclopedia[/ame]
[ame=http://en.wikipedia.org/wiki/Syriac_Military_Council]Syriac Military Council - Wikipedia, the free encyclopedia[/ame]
Both sides who claim either all Arabic Christians are Arabized or all of them are real Arabs have agendas.