If we follow your methods we WILL reach there, that's the point.
The way to prevent terrorism is to minimize its impact, make it worthless. A way to have fewer terrorists is to not mistreat the population that the terrorists seem to be coming from, stop giving validating the message of the terrorists.
If you think this is what i'm talking about than you got it all wrong!
To stop the problem before our borders is not mistreatment.
To kick out someone whom already expelled, is not mistreatment.
To expel the criminals, the madman's, the fanatic's are not mistreatment.
To keep an eye in the newcomers is not mistreatment.
To think twice whom we let in is not mistreatment.
To keep the refugees within camps with conditions, worthy of human begins is not mistreatment.
To take terrorism seriously is not mistreatment.