Many studies have covered aspects of military intelligence available to Britain and her allies during the Second World War. This distinguished book provides a succinct and authoritative survey of the vital role Ultra played in achieving final victory.,

When war began Britain was as ill-prepared in intelligence as armaments. Civilian scientists had discovered the principle of radar in the mid-1930s, but everything had to be learned from scratch in the heat of emergency. First signs of improvement came in mid-1941, when Ultra targeted naval vessels and bomber aircraft onto so many of Rommel's supply ships that the Africa Corps almost withered on the vine.

From then on intelligence played an increasingly indispensable part in final victory. Ultra won the Battle of the Atlantic, driving U-boats back to coastal waters by June 1943. Ultra confirmed the whereabouts of the German tanks as Montgomery planned the breakthrough to Alamein. Only 'Bomber' Harris refused to give intelligence the credit it deserved; on the basis of new evidence this fascinating book strongly reinforces criticism this costly mistake.