That article contradicts itself somewhat! He says that bombing has killed 20,000 ISIS troops and then that it doesn't work and that it kills civilians. It depends on where you are bombing.
Tactical bombing in support of ground troops is very unlikely to kill civilians as they will have left active fighting zones. In these areas there are going to be large numbers of ISIS troops who are legitimate military targets and bombing them gives a huge advantage to the opposing troops.
The ISIS supply lines are very long and attacking these would force the ISIS troops to withdraw or would at least affect their fighting ability - you can't fight so effectively if you're short of ammunition. There have been some reports that US and UK special forces have been operating behind ISIS lines to disrupt this fighting ability. giving friendly troops the ability to fight like the Long Range Desert Group did in the last war would help.
The terrain is ideal for it and ISIS have no airforce to counter it while Iraqi and Kurdish forces have either their own or US/UK air forces to call on for backup. There are plenty of ground troops available, especially in Iraq, if the religious problems between different units could be ironed out.
It is surely better to fight ISIS now while there are local troops available to bear the brunt of the fighting and we still have access to Middle Eastern oil. If we allow ISIS to take over and gain access to all the oil fields plus the military stores of the Iraqis, Saudis and Gulf States they will have enough munitions to go into Iran and we will not have enough oil to take them on. And no oil would mean economic collapse for us as well.
We have two options: to fight them now or to invite them in and convert to Sunni Islam en masse. Thinking about it there is a third option and that is to die!