Hunting for polar convoys. Scandinavian bridgehead of the Third Reich

The Norwegian Wehrmacht campaign was the first combined operation of the army, aviation and navy in the history of military art, and Norway itself is the “unsinkable aircraft carrier” of the Third Reich. The attacks of the polar convoys, which delivered about half of all strategic cargoes on Lend-Lease in the USSR, including the legendary PQ-17, Luftwaffe and Kriegsmarine led precisely from bases on the Norwegian coast. This book, based on declassified archival documents, answers the most controversial and complex issues of the Germans by the Scandinavian bridgehead.
What helped to lightly capture Norway and why did the German losses exceeded the losses of the allies a third? What is the true role of the Scandinavian bridgehead in Hitler’s plans and why in 1941 his submarines failed to prevent transportation to the Soviet Union? What were the strategy and tactics of actions against polar convoys? Why, despite the deterioration of the situation on the fronts, the German command increased the group of U-Botts in the Arctic? Why did not a mine war bring Kriegsmarine tangible results, and the operations of surface ships (including the famous "tyrpica") against the polar convoys invariably ended in failure? Finally, why, having the opportunity to control the movement of convoys almost all the way, the Germans could not disrupt or at least seriously reduce deliveries to the USSR?