Britain was the first country to come under sustained ballistic missile attack, during 1944-45. Defence against ballistic missiles has been a persistent, if highly variable, subject of political policy and technical investigation ever since. The British Second World War experience of trying to counter the V-2 attacks contained many elements of subsequent responses to ballistic missile threats. After the war, a reasonably accurate picture of Soviet missile capabilities was not achieved until the early 1960s, by which time the problem of early warning had largely been solved. From the mid-1960s...