The Syrian air force has no reservations about attacking ISIS in cities.

[pampango]

While many of us wonder how US air power will be used in urban areas without causing large scale civilian casualties, Mr. Assad is going full-speed-ahead in attacking ISIS cities from the air.

Syrian military plane crashes in Islamic State stronghold, say activists


An Islamic State militant and Raqqa residents hold pieces of wreckage from a Syrian military plane.

A Syrian military aircraft has crashed into the de facto capital of Islamic State (Isis), killing at least eight people, as thousands of residents fled to nearby villages in anticipation of expected US air strikes against the militants, activists said.

It was not immediately clear whether the plane that slammed into the north-eastern city of Raqqa was hit by anti-aircraft fire or experienced a technical failure, according to an activist based in the city and the Britain-based Syrian Observatory for Human Rights on Tuesday.

As international attention has zeroed in on the extremists, the Syrian government, which largely shied away from bombing the group's territory for more than a year, has begun targeting cities and towns under the militants' control more frequently.

Those government strikes, and perhaps the prospect of a US-led aerial campaign that is all but certain to target Raqqa, have prompted many residents to pack up and move to outlying villages, according to Alwfaa and another resident. ... Previous Syrian air strikes have killed dozens of civilians in Raqqa. Alwfaa said residents feared US strikes would cause even more damage.

http://www.theguardian.com/world/2014/sep/16/syrian-military-plane-crashes-islamic-state-stronghold-raqqa

It is one thing for the US to attack ISIS fighters who are in open terrain attacking Kurdish or Iraqi forces. The tougher question is how effective bombing from the air will be if and when the US decides to support Iraqi or Kurdish fighters who are retaking urban areas. For the most part there are few civilians in the open terrain where the current military fronts are, but that will change when the fighting reaches urban neighborhoods.