There's apparently three thousand "persons of interest" in terms of radical islamist sentiment. There's certainly a lot of sentiment about rounding these people up, with little analysis of the detail. How would this work from a practical point of view. What effect will it have ? Deport them ? To where ? How to get the receiving country to accept them ? The UK nationals, where will they go ? How will you get them all at once, without a load of them going to ground ? Will their children go with them ? why would this not just backfire and recruit more terrorists, like it did in the 1970's when we did this ? Why should it be limited to Islamists ? In the 1970's we rounded up people on both sides.