The Syrian crisis has turned into a civil war. The Syrian Free Army, the main armed opposition in Syria, has launched consecutive attacks on the suburbs of Damascus and even plans to shell the presidential residence. So bloody has been the recent violence that on Sunday UN Secretary-General Ban Ki-moon expressed alarm at the situation in Syria.

In the beginning, the armed conflict was confined between Syrian government forces and loosely knit opposition fighters. But with the help of foreign forces, the opposition is much stronger now and the conflict has become a doing-dong battle for the control of Syria.

The opposition is gaining increasing international recognition. On Nov 11, 2012, some Syrian opposition groups established the National Coalition for Syrian Revolutionary and Opposition Forces in Doha, Qatar, with the former imam of the Umayyad Mosque in Damascus, Moaz al-Khatib, being elected its president.

The Gulf Cooperation Council immediately recognized the coalition as the legitimate government of Syria. Later, the Arab League, the United States, France and Turkey recognized the coalition as the "true representative" of the Syrian people. On Nov 19, the European Union recognized it as "legitimate representatives of the aspirations of the Syrian people" and said it was ready to help it build relationships with other countries.

But there still are great differences among Syria's opposition forces. The al-Nusra Front and 13 other armed groups, for example, have rejected the Syrian National Coalition as the "true representative" of the Syrian people.

The role of external forces has been (and will be) crucial to the Syrian crisis. The opposition and their foreign patrons are continuing their fight against the Bashar al-Assad government. The Syrian government and the opposition both are trying to get the support of external forces to consolidate their positions.

The Syrian government wants countries opposed to war, such as Russia, China and other emerging economies, to restore normalcy. And the opposition forces are determined to overthrow the Assad government with the help of the US, NATO, Saudi Arabia, Qatar, Turkey and some other countries. This makes the Syrian crisis akin to the one in Libya before the eventual overthrow of Muammar Gadhafi.

At present, on the table are both the diplomatic and military resolutions to the Syrian crisis. Many believe that with the re-election of Barack Obama as US president, Washington now has a free hand to deal with Assad, while some analysts say it is time the Syrian crisis was resolved through military intervention. France has emerged as the most prominent backer of Syria's armed opposition. And NATO has approved Turkey's request to deploy Patriot missiles along its border with Syria to protect it from potential cross-border attacks and repeatedly called for establishing a "no-fly zone" in northern Syria.

Obama, during his first term as US president, adopted a policy of strategic retreat from the Middle East, vowing to recalibrate America's relationship with the Islamic world, and announced a near complete withdrawal of US combat troops from Iraq. During the Libyan crisis, the US passed on the "authority" of launching air strikes to NATO. Washington's response to the Syrian crisis, though strong in terms of words, has not been of military intervention; it claims to have offered only non-combative support, such as communications equipment, to the Syrian opposition forces.

Obama is likely to refrain from being involved in a war in the Middle East even during his second term in office, because he needs to rebuild Washington's Middle East strategy, restore American prestige and repair the US' relations with Middle East countries that have been weakened by the "Arab Spring".

There is no guarantee, though, that the US will not use force against the Assad government. There is only a possibility that as long as a non-military solution is likely, Obama will not intervene militarily in Syria for fear of igniting a powder keg in the Middle East. Of course, NATO, Turkey, Saudi Arabia, Qatar and the Syrian opposition want the US to use force to oust Assad. But it seems that both diplomatic and military solutions are still on the table.

The risk of the Syrian crisis spilling over to other Middle East countries is increasing. The military conflict in Syria could spill into Iran, Iraq, Lebanon and other neighboring countries. And once Hezbollah and Hamas, and Israel are drawn into the conflict, the Middle East will be engulfed by chaos and more bloodshed. To prevent the Middle East from sliding into turmoil, the US and Russia tried to promote a peaceful transfer of power in Yemen, which was successful.

The Syrian crisis seems to have spiraled out of control and led to ethnic conflicts, and the Kurdish problem has become another important factor in the crisis. The Kurds in Syria have taken advantage of the turmoil to consolidate their position, which is perceived as a big threat to Iraq, Turkey and Iran. These three countries will not allow the Kurds in their territories to unite with those in Syria to establish a Kurd state.

So if the Syrian crisis continues for long, the consequences for the entire Middle East will be disastrous.

The author is a researcher at the Institute of West Asian and African Studies, affiliated to the Chinese Academy of Social Sciences.