Turned the Tide in the Second World War (2013)
British Prime Minister Winston Churchill and President Franklin Roosevelt had been trying to bring about "jointness" since the Atlantic Charter. Overall command of Torch went to the American General Dwight Eisenhower, who was headquartered at Gibraltar. Also different from Dieppe was the distance and scope of Torch; so many different ships had to be in place at the right time, including landing craft for the soldiers to reach the beaches.
By 12 November 1942, the approaches to Casablanca in Morocco were secured, but the landings in Algiers and Oran were much more difficult due to increased enemy resistance. However, in three days, all three target areas in North Africa were secured, and the Allied ground forces started moving inland.
The Allies learned quite a few important lessons in terms of amphibious campaigns in North Africa: first, be sure to have control of the air, and if there were enemy air bases, take them. Second, be sure to have a command ship (a "Floating Headquarters"; the US didn't have a command ship during Torch). Third, it was sheer folly to attack an enemy in a fortified harbor, even if taking enemy-held beaches was very difficult. Complicating matters was that weather and geography was a potential additional enemy for the Allies when moving on an enemy shore. Lastly, the Allies didn't yet know how their strategies/tactics would work against entrenched German troops on a beach . . . Torch, despite the casualties, and been a relatively easy campaign for the Allies.
However, Operation Overlord looked beyond-foreboding, in that the Allies experienced extreme resistance in Italy from German troops . . . the assumption was that German resistance would be far-greater in France. The Western Allies had no way of knowing that they would be able to take five separate beach-landings from the Germans, and start to pour inland like a breached dam, meeting resistance and swirling past obstacles. The ground forces would surge through gaps and places of least resistance, covered by air power, tanks (for the British), and mobile artillery. By the end of June 1944, Allied forces were twenty miles inland . . . by 25 August 1944 US and Free French troops were in Paris. So, why was Operation Overlord successful in the face of the feared German resistance . . . it started with Command-and-Control . . . without it, Operation Overlord would fail.
Air, sea, and deception/intelligence were factors that they could at least largely control; out of their control was the weather and the nature of German positioning and their response to the landings . . . the capacity of the Wehrmacht to strike fast (like at Anzio) had to be blunted. Also, German communications had to be crippled to-and-from the Atlantic / English Channel shores. Therefore, Eisenhower ordered the US Army Air Force (USAAF) and Ramsay the Royal Air Force (RAF) to strategically bomb bridges, roads, railroads, and known key communication centers in order to paralyze military transportation/communication networks for the Wehrmacht.
In the end, Hitler had made a series of decisions that benefited the Allies, in that he created a strategic situation that Germany would be weak everywhere, and strong nowhere, which was the exact opposite of Frederick the Great's military philosophy. Therefore, German defenses at Normandy were not strong enough on the shores, and not strong or mobile enough inland. So while the Allied invaders were very smart, well-orchestrated, and in command of the air and sea, they were also very, very lucky.
There were three amphibious landing forces in five beaches for D-Day, 6 June 1944. The westernmost of the beaches was Utah Beach; at the end of the day, US forces had moved five miles inland. Having reached that point, the US troops at Utah would not be easily dislodged; Utah was by far the smoothest amphibious attack in all of WW II - the 8th and 27th Infantry regiments lost a total of 12 men (pictured: General Patton in 1943 - to the right was General Theodore Roosevelt Jr., who would be the first high-ranking officer to set foot on Utah Beach).
Therefore, Britain was massively invested in deception, intelligence, Command-and-Control, signals, beachmasters (the US had none), mine clearance, as well as specially-designed tanks. Nicknamed "Hobart's Funnies", the British had a tank for almost any purpose, such as flail tanks, flamethrower tanks, and tanks that laid a layer of "carpet" so vehicles could get off the beach (pictured). With these specially-designed tanks on the beach, Germans fighting from concrete bunkers were not safe . . . at Gold, Juno, and Sword beaches, Rommel's "Outer Crust" strategy (keep the Allies on the beaches) quickly failed.
Only 5 of 32 tanks made it to the beach, and over 60% of the howitzers sunk.
American destroyers came within 1000 yards offshore to fire on the German bunkers, endangering the ships to minefields in the water near the shore. The initial landing at Omaha featured 34,000 men and 3300 vehicles with a similar number in reserve. Desperate shelling by the destroyers plus USAAF tactical bombing plus re-establishing order on the beaches finally cracked the German coastal defenses at Omaha. US troops got off the beaches, up the bluffs, and held a position only a mile inland. The German panzers could have easily pushed the Americans back to the beach, but Hitler refused to authorize any movement.
The 1st and 29th Infantry Divisions had taken Omaha Beach at bitter cost, and it was a close-call; Eisenhower was clearly disturbed the next day when he personally surveyed the situation. The 1st & 29th had 2400 killed, wounded, or captured; compared to large Civil War battles, or to such World War I disasters as the first day of the Somme, or Operation Bagration in the Eastern Front, those casualties pale in contrast . . . but Omaha Beach was by far the most deadly of the five beach landings on D-Day.
There was poor battlefield management at Omaha Beach, with too much self-confidence in play, which was never wise against the Wehrmacht. The naval bombardment beforehand was light, and cloud cover doomed the USAAF/RAF bombing runs. With the high waves/tides, it was sheer folly to order the tanks and howitzer craft in the sea 5000 yards away. The US had no flail or wire-cutting tanks, and General Bradley and his staff was unaware that the German 352nd had just moved behind Omaha beach in support.
The US troops at Omaha Beach achieved their objective without the luck, support, planning, and weapons that were present at the other four beaches. Depending on sources, between 132,000 and 175,000 Allies swarmed ashore at Normandy on 6 June 1944, taking approximately 5000 casualties, which was far-less than planning estimates. On 27 August 1944, Eisenhower was in Paris (which had been liberated two days prior); the Wehrmacht fought ferociously in defense with remarkable tactical efficiency, most notably in the Battle of the Bulge. For the rest of WW II in Europe, amphibious attacks were no longer needed; much of what was used at D-Day was sent to the Pacific.