 Complete the following phrase:  On 28 March 1981, Powell gave a speech to Ashton-under-Lyne Young Conservatives where he attacked the conspiracy of silence between the government and the opposition over the prospective growth through births of the immigration population and added, We have seen nothing yet is a phrase that we could with advantage repeat to ourselves whenever we try to form a picture of that future. He also criticised those who believed it was too late to do anything and that there lies the certainty of violence on a scale which can only adequately be described as civil war. He also said that the solution was a reduction in prospective numbers as would represent re-emigration hardly less massive than the immigration which occurred in the first place. The Shadow Home Secretary, Labour MP Roy Hattersley, criticised Powell for using Munich beer-hall language. On 11 April, there was a 