Powell's opposition to mass immigration derived from his nationalist outlook. Powell claimed that the children of Commonwealth immigrants to Britain did "not, by being born in England, become an Englishman. In law he becomes a United Kingdom citizen by birth; in fact he is a West Indian or an Asian still". Powell claimed that Commonwealth immigration to Britain post-1945 was "in point of numbers out of all comparison greater than anything these islands have ever experienced before in a thousand years of history". Powell asserted that as the immigration was concentrated in urban areas, the result would be violence: "I do not believe it is in human nature that a country... should passively watch the transformation of whole areas which lie at the heart of it into alien territory". Powell claimed that his warnings were political: