The Conservative Party failed in its manifesto to commit itself to breaking the link between work and citizenship. Instead, David Cameron promises to reduce net immigration to the tens rather than the hundreds of thousands we have seen in recent years. But will that commitment be sharpened to below 40,000 and so prevent the population growing and breaking the 65 million and then the 70 million barrier? Voters need to apply pressure to local candidates to get a commitment on this score. With a double lock on immigration, our politicians must then deal honestly with the question of integration. Here is another of the political classes' greatest failures.