Lebanon, which was occupied militarily by Syria from 1976 to 2005, has adopted a policy of "disassociation" towards its neighbour’s crisis, fearing the chaos could spill across its borders. There have already been armed clashes between Assad supporters and Syrian rebels in the north of the country, where rebels base their operations and home to some 30,000 Syria refugees.
Damascus has already accused Lebanon’s political factions of sending arms and terrorists across the border into Syria to boost the rebellion. If it is pushed to take action, Syria could once again send its army into Lebanon under the pretext of hunting down rebel fighters. Both countries have recently traded accusations of border violations.
If Assad falls, Hezbollah will lose a key ally across the border and may be tempted to launch a coup to prevent an alliance between Sunni groups in Syria and Assad’s opponents in Lebanon. This could risk triggering a civil war between pro and anti-Syrian forces in Lebanon.
The situation on the border between the two countries, who are officially still at war with one another, is relatively calm. However, Israel has recently sent reinforcements to be deployed along its northern border with Lebanon and Syria.
Tel Aviv is concerned that the Golan Heights, which Israel seized from Syria in the Six Day War of 1967, will become a focal point for an attack against its borders. The Jewish state also fears that the toppling of the secular Assad regime, which has always guaranteed relative peace, will see it replaced by Islamist rulers more aggressive towards Israel.
For the Israeli government, the worst case scenario in a post-Assad Middle East would be Syria’s vast arsenal of chemical weapons falling into the hands of Islamist radicals with links to al Qaeda. Or to the Iran-backed Lebanese militant group Hezbollah, Israel’s sworn enemies.
Jordan claims it is now home to more than 140, 000 Syrian refugees, including 36,000 who are officially registered with the UN. The country’s capital Amman is also home to several hundred deserters from the Syrian army. There have been reports in recent days of military skirmishes on the border between the two countries.
According to analysts, Amman’s greatest fear is the infiltration of Syrian agents among the floods of refugees, there to create unrest as revenge for Jordan’s support of the anti-Assad policies of both Turkey and the US. Jordan is also anxious about who will gain control of Syria’s biological and chemical weapons, should Assad fall.
The kingdom could suffer long lasting instability in the case of civil war and the resulting exodus of refugees from a post-Assad Syria. The country is already struggling to deal with a humanitarian crisis at present.
Iraq, a key member of the ‘Shiite Crescent’, or ‘Shiite Axis’, which stretches from Tehran to Damascus, is the only one of Syria’s neighbours who continues to support Assad. According to numerous reports, hundreds of jihadists have crossed into Syria from Iraq to join the fight against Assad, making the border a sensitive and crucial concern. The UN says that, in the last three weeks, more than 22,000 Iraqis living in Syria have fled the violence and returned to their home country.
An exacerbation of sectarian tensions between Sunni and Shiite Muslims and increasing instability around the border region could play into the hands of Islamist Jihadists, who are already in open war against Baghdad.
In the case of a post-Assad meltdown the Kurdish controlled part of northern Iraq, which is already quasi-independent, could forge connections with the Kurds in Syria. Another concern would be the rise of the Syrian Muslim Brotherhood in Damascus and the instillation of a new Sunni regime hostile to Iraq’s Shiite Prime Minister Nouri al-Maliki.
Turkey, which shares a 900km border with Syria, has played a major role in aiding the Free Syrian Army, whose command base is within its territory. Turkey has also given sanctuary to 50,000 Syrian refugees and numerous Syrian army deserters along its border region. Ankara has repeatedly called for its former ally Assad to step down.
Ankara is concerned about the risk of a mass influx of refugees from the besieged Syrian city of Aleppo, currently the scene of fierce fighting between rebels and government troops. Like Jordan, Turkey also fears a revenge campaign by Syrian secret services.
The question of Kurdish autonomy raises the hackles of Turkish authorities, who fear a partition of Syria and the creation of a “Kurdistan” with the north of Iraq. This would boost the determination of the Kurdistan Workers Party PKK, which has been involved in an armed struggle against Turkey in a bid for Kurdish autonomy, testing the limits of Turkish patience.