Whereas a `closure' (q.v.) imposed on the territories prevents Palestinians from coming into Israel, `encirclement' totally closes off every town and village there – nobody comes in, and nobody leaves. And to make all this more effective, the army destroys approach roads to the villages, or renders them impassable with huge cement blocks, deep ditches and high mounds of earth. Necessity means that alternative routes are developed, roads so full of potholes as to wreck the Palestinians' cars – but worse than this: to create deep hatred and a sense of all-pervading frustration. As one checkpoint commander put it: “They know there's an encirclement, so it's better if they all stay at home”.