They do not intend to take serious action against ISIS
Earlier they formed a so-called global coalition against Syria with great fuss and uproar. They gathered 30, 40, 50 countries, but they could not do a damn thing against Syria. The same is true of Iraq. They do not intend to take serious action there either. The action that was taken against ISIS and that broke its back was not taken by the Americans. They themselves and ISIS militants too know this very well. The people of Iraq too know this very well.
The Americans know that it was the people of Iraq, the Iraqi Armed Forces and the popular forces who perfectly understood how to fight against ISIS. They have fought it and they have dealt serious blows to it so far. From now on too, they will continue to deal such blows. They will see this.
With this move, America wants to find an excuse to do the same thing to Iraq and Syria that it is doing to Pakistan. They enter Pakistan without any permission despite the existence of a well-established government and a strong army - the Pakistani army is a strong army - and they bomb wherever they want.