Operation Sledgehammer

Operation Sledgehammer was a World War II Allied plan for a cross-Channel invasion of Europe, as the first step in helping to reduce pressure on the Soviet Red Army by establishing a Second Front. Essentially, Allied forces were to seize the French ports of either Brest or Cherbourg during the early autumn of 1942 along with areas of the Cotentin Peninsula, and then amass troops for a breakout in the spring of 1943, and as such, was a contingency alternative to Operation Roundup, the original Allied plan for the invasion of Europe in 1943.

The operation was eagerly pressed for by both the United States military and the Soviet Union but rejected by the British. As a result, Sledgehammer was never carried out; in addition, planners decided it was impractical. This perception was reinforced by the failure of the smaller Dieppe Raid, in August 1942. Instead the British proposal for an invasion of French North Africa took place in November 1942 under the code name Operation Torch.

After the United States entered World War II, the U.S. Joint Chiefs of Staff pressed for an invasion of mainland Europe via the English Channel "as soon as possible", i.e. the early part of 1942. The British were, however, reluctant, as it was felt that other places had a higher priority, the time was not right and insufficient men and landing craft were available. British officials pressed for action in North Africa which would allow relatively inexperienced American forces to gain experience in a less risky theatre while gradually building up overwhelming force before engaging Germany head on.

The U.S. tended to regard this reluctance as an example of British caution but since at the time they lacked the resources to carry out such an operation themselves, the result was stalemate, along with increased pressure on the British, which began in March 1942 with a letter from President Roosevelt to Winston Churchill:

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