Why the Allies did not try to retake Norway

Why did the Allies not make a second attempt to take Norway after the United States entered the war?

Because an entrenched German force in Norway's difficult terrain would make a renewed invasion disproportionately costly and complex.

An Allied return to Norway would have become an operational nightmare after Germany fortified the country and stationed many troops there. Norway's terrain makes amphibious entry, movement, and sustainment exceptionally difficult. This later problem differed from the surprising German success in 1940, which depended heavily on the Norwegian government's mishandling of mobilization. A more timely Norwegian call-up could have defeated the original invasion, but once Germany was entrenched the cost of reversing it became far higher.