.. the do-nothing, hand-wringing favoured by Turkey's international allies may not be politically sustainable much longer as the Syrian crisis inexorably expands not just into Turkey but into Iraq, Lebanon and the Israeli-occupied Golan Heights.The fact is that the USA is not taking a "do-nothing" approach to the Syrian Civil War. It already has tacitly allowed Saudi Arabia and Qatar to pour in weapons and finance for Sunni fundamentalists, has CIA advisers on the ground to co-ordinate them and has remained firm on the call for Assad's regime to be destroyed from the outset.
That aim is one in line with its geopolitical interests in removing Iran's main ally in the Middle East in Syria which Russia and China do not want. The US approach is not based on doing nothing ( that has been more Russia's and China's position ). The US and Britain want to steer the war to the pursuit of its interests by backing proxies on the ground.
Whether hundreds of thousands of ordinary Syrian civilians perish is of less interest other than as material for propaganda. As with British Foreign Secretaty William Hague, they will robotically repeat the same line "Assad must go". That was the game plan from the beginning and not a ceasefire that could have saved many lives.
The wider plan stretching from the Middle East into Central Asia is to curtail Iranian influence to the west by toppling the Assad regime and to the east by maintaining a Afghan client state and blocking off Iranian gas exports to Pakistan and India by getting the TAPI pipeline constructed. This dovetails with the sanctions policy.
Syria is a proxy war in the contest for hegemony over the oil and gas of the Middle East and Central Asia. Iran is the ultimate target for regime change and with the challenge posed by Russia and the growing power and wealth of China, they will pursue "pro-active" foreign policies to do so. This is the lethal consequence of overdependence upon oil to fuel high octane consumer economies.