How important was the Suez Canal to the Allies during WWII?

Question

The Suez Canal allows one to travel from the Mediterranean or North Atlantic to the Indian Ocean without having to circumvent the continent of Africa. A ship traveling from the UK to India could expect to save 2 weeks travel time by using the canal. This also pertains to the Persian Gulf.

After the outbreak of WWII the Axis sent troops to North Africa(1940) to capture the canal. Fighting in North Africa went back and forth with neither side being able to vanquish the other. In the summer of 1942 the axis was poised to break through. The Axis offensive launched on May - July 1942 saw Allies rolling back.

• May 26: Axis forces assault the Gazala line, the Battle of Gazala and Battle of Bir Hakeim begins
• June 11: Axis forces begin offensive from "the Cauldron" position
• June 13: "Black Saturday". Axis inflicts heavy defeat on British armoured divisions
• June 21: Tobruk captured by Axis forces
• June 28: Mersa Matruh, Egypt, falls to Rommel.
• June 30: Axis forces reach El Alamein and attack the Allied defences, the First Battle of El Alamein begins
• July 4: First Battle of El Alamein continues as Axis digs in and Eighth Army launch series of attacks
• July 31: Auchinleck calls off offensive activities to allow Eighth Army to regroup and resupply

The Allied lines held. In August of 1942, Montgomery was appointed commander of the British Eighth Army and on Oct 23 1942, he launched a major offensive from El Alamein which forced the Axis retreat. Operation Torch Nov 8 - 10th landed Anglo American troops In French North Africa (Morocco and Algeria) cutting off the Axis forces in Tunisia. On May 13, 1943 Axis forces in North Africa surrendered.

How Important was the Suez Canal to the UK, vs British Empire? How important was it during WW2 vs after WW2? In a related question: Why did the Allies Invade French North Africa?, it was noted that all senior American military officers objected to the allies landings in North Africa, as all of the senior British military officers and Chuchill insisted on the North African invasions. It took FDR to order his officers to prioritize operation Torch to break the impasse. Nobody including me in that segment mentioned the Suez Canal. The primary reason the Axis and Allies were in North Africa. Clearly the Suez Canal was a vital interest to the British Empire before WWII, It was perhaps even more important after WWII for oil, even though the British began to disengage from the empire beginning in 1945 with the election of Clement Attlee as PM replacing Churchill.

British Empire
The pro-decolonisation Labour government, elected at the 1945 general election and led by Clement Attlee, moved quickly to tackle the most pressing issue facing the empire: Indian independence.[183] India's two major political parties—the Indian National Congress (led by Mahatma Gandhi) and the Muslim League (led by Muhammad Ali Jinnah)—had been campaigning for independence for decades, but disagreed as to how it should be implemented.

• Oil was discovered in Saudi Arabia for example in 1938, but in Iran in 1908.
• The first British North Sear oil well dates from 1967.

My thought is oil transportation wasn't the primary value of the Suez Canal during WWII because American oil, amounted in all "to 6 billion barrels, out of a total of 7 billion barrels consumed by the Allies for the period of World War". (see How Important Was Oil in World War II?

Question: How important was the Suez Canal to the Allies during WWII?

Was it's primary value in the maintenance of the British Empire? Economically tying together the UK with it's most important colonial possession India as well as economically important China in peace time for example.

Answer 1

The Suez Canal was important mostly to the British, but it was very important to them. They needed to move large amounts of raw materials to Britain, where their industries were, and move the products to where the fighting was. This was strange to much of the US Army leadership of WWII, and they took some time to take it in.

The Americans were used to being based on a continent that had sources of almost everything, and had trouble adjusting to the way that the British got so much from overseas. This wasn't just for "ruling the empire", it was critical for all sorts of materials and manpower.

While the British Isles had quite a lot of manpower and lots of coal, they were deficient in many of the other materials needed to create military power. British power was crucially dependent on sea transport, and there was always a shortage of ships. If ships coming from India and Australia have to go around Africa, lots of them are occupied making that voyage, and the number of cargoes they can deliver per year goes down.

Britain imported food and raw materials and produced manufactured goods - in wartime, largely weapons and munitions. Those then had to be shipped to where they were needed, along with troops to use them.

For the Germans, taking the Suez Canal would badly damage the British ability to supply armies in the Middle East from the UK. That involved sailing around Africa and using the canal at the end of the voyage, but that was better than not being able to get stuff there at all.

The Germans would also gain a relatively easy route to Iran for oil, which the Germans were always short of. Getting it back to Germany would have been the next problem, but Rommel wasn't immediately worrying about that. Taking Egypt would also have deprived the British of bases, ports, hospitals, training centres and other infrastructure that contributed to military power.

For the British, holding Suez was only part of the problem. If Italy could be removed from the war, and the German forces in the Mediterranean Sea reduced sufficiently, it would no longer be necessary for supplies to sail round Africa. This would significantly increase the throughput of the available shipping, allowing the generation of more military power.

This was why they wanted the invasions of French North Africa and Italy: to increase the amount of military power they could wield. Without those things being accomplished, the Suez Canal was only useful for bringing troops and supplies to the Eastern Mediterranean around Africa - but without it they would have had to concede the entire Mediterranean.

I'm not clear as to just why it took time to get this idea across to the US generals. The US Navy understood the idea thoroughly: it's basic naval grand strategy.

Source: Masters and Commanders, by Andrew Roberts, an excellent book on Allied conferences and high-level decisions in general.

Advocating Overlord by Philip Padgett discusses a related subject, the debate within and between the US and the UK about invading Europe. Padgett makes the point that the UK felt that a cross-channel invasion was too risky - understandable given their last 30 years' experience fighting in France - and were focused on invading through the "soft underbelly". This required the Med be kept open. They also (correctly) felt that US forces needed experience before any invasion of Europe or North Africa was attempted.

Addition: Taking the Suez Canal would also have given Germany and Italy the potential for access to the eastern coast of Africa. If they'd achieved that, they could have joined forces with the Japanese Navy, which was well worth avoiding.