From a retired Army guy:
It’s an Indian fight — a violent and bloody struggle against an enemy without morals or values as we understand them, and a way of life alien to us. In an Indian fight they took scalps; now they take heads.
The US Army fought the Indians on this continent for 115 years; the British Army and Colonial militias had fought them for 150 years before that. The War on terror is going to be long and bloody, and fought on many fronts. It won’t be won in the next four years, but it could be lost.