The Invisible Chokepoint

As East and West start to eye strategic maritime passages, there is a distinct absence of attention to the Cape. But that cannot last forever.

Robert Duigan

By 

Robert Duigan

Published 

March 26, 2025

The Invisible Chokepoint

In his master work The Influence of Sea Power upon History, Admiral A.T. Mahan drew a thesis on Britain’s rise to global dominance which has become so obvious one forgets it was once a novel theory: “control of the sea by maritime commerce and naval supremacy means predominant influence among the nations; it has been so in the past, and it will be so in the future”.

In the wake of the new Trump presidency, there is a perceived retreat from aggressive foreign policy and the liberal international system as a whole, but this is not the full picture - there is an increased focus on maritime chokepoints; a return to a harder approach of strategic “realism”. The Federal Maritime Commission has been tasked with examining seven of these: the Northern Sea Passage, the English Channel, the Malacca Strait, the Singapore Strait, the Strait of Gibraltar, the Panama Canal, and the Suez Canal.

But there is a blindspot here, one which could cost them if they cannot incorporate it into their calculations - the Cape of Good Hope. Fortunately, China sees no urgency in the South Atlantic either, but the clock is ticking, and with the Suez increasingly under Eastern control, it may be time to think more seriously.

China

China has had its eye on maritime chokepoints for years now, and America is only just starting to play catch-up. With Obama’s pivot to Asia, the United States was largely preoccupied with Russia.

China sees themselves as the natural centre of the world, and their gravity will pull all into its orbit. Certain establishment types in America had, for some reason, been under the impression that sufficient economic development would change this, and magically transform them into Western Liberals.

This “pivot” seemed to ignore China’s basic stance on the matter - in 2013, the CCP issued an ideological directive (known as “Document 9”) to oppose all elements of Western political culture and values in the Liberal International Order.

They have placed a great deal of focus on their immediate surroundings, but not exclusively. The 2019 Defense White Paper emphasizes safeguarding "strategic passages of importance".

The PLA Navy, with a fleet of over 350 ships, conducts numerous regular patrols in the South China Sea and Indian Ocean, often harrassing vessels belonging to neighbouring countries. But victims of this perceived sphere of influence go beyond its immediate neighbours.

In February and March this year, a Chinese naval task group (destroyer CNS Zunyi, frigate CNS Hengyang, and replenishment ship CNS Weishanhu) conducted a military circumnavigation of Australia, straight through Australia’s Exclusive Economic Zone, conducting live-fire drills in the Tasman Sea that disrupted commercial flights. Australia and New Zealand closely monitored the group, but did nothing, much as they have done for the rest of the several harrassment excursions seen over the past few years.

They appear to see a long term plan to surround Australia, with most of its neihgbours to the north, where the vast majority of Australian shipping goes, signing up to defence, finance or port development contracts of one form or another (fortunately Indonesia is leaning more Western in its defence strategy).

Economically, China invests heavily, controlling 12.6% of global port throughput via state firms like COSCO. Diplomatically, it engages 10 ASEAN nations, with trade reaching $975 billion in 2022 (ASEAN Secretariat). An unexpected focus is the Arctic route, with potential to cut shipping time by 20-30% (Chinese Academy of Sciences, 2021), reducing reliance on traditional chokepoints.

The “maritime silk road”, part of the Belt and Road Initiative (BRI), enhances connectivity across Asia, Europe, and Africa. The 2015 "Vision and Actions" document outlines infrastructure and trade goals of a fairly comprehensive nature, not limited simply to port infrastructure. They had invested $200 billion in 42 ports globally by 2023, including Hambantota (Sri Lanka) and Gwadar (Pakistan), handling 5% and 2% of regional throughput, respectively.

The initiative spans 65 countries, covering 62% of the world’s population and 31% of global GDP. Security-wise, bases like Djibouti support 2,000 troops, protecting sea lanes, with trade via BRI routes hitting $1.5 trillion in 2022.

As a result of the Gaza war, the West has largely lost control of the Red Sea trade route, due to harrassment from Iran-backed Houthi rebels. But in the longer term, Egypt, which controls the Suez Canal, is also leaning ever more towards the East.

China is involved in 62 port projects in Africa, including two in Egypt, which has applied to join the BRICS alliance, which is not simply a loose allegiance, but a cluster of nascent organisations designed to align trade, development and finance, and ultimately military might.

Historic ties also count. Egypt was the first nation in the Middle East or Africa to recognise the People’s Republic of China, who aided them in the Suez Crisis, including diplomatic support and a gift of 20 million Swiss francs. Egypt backs China’s position on all foreign policy initiatives, including the South China Sea disputes.

China and Egypt signed a Comprehensive Strategic Partnership in 2014, a key feature of the Maritime Silk Road initiative. The first significant joint naval exercise took place in 2019, followed by another in 2024, under the 2014 framework. There is also much speculation about J-10C fighter sales, as Egypt has begun diversifying military hardware away from U.S. reliance.

The Suez Canal Economic Zone hosts over 180 Chinese companies, with investments exceeding $3 billion since 2008. Projects include industrial zones like TEDA Suez, which China plans to expand by 3 square kilometers, reinforcing Egypt’s role as a logistics hub. Last year, Egyptian Prime Minister Madbouly signed $1 billion in contracts with Chinese firms for new SCZone projects during the Forum on China-Africa Cooperation (FOCAC).

China is already their biggest trade partner, at 12-15%. 60% of China’s exports to Europe pass through Suez, and they have made piracy a high priority in the region. But China’s anti-piracy efforts in the Red Sea are selective.

The Iranian-backed Houthi forces have been harassing Western trade in the region, while offering a free pass to Russian and Chinese ships. On January 19, 2024, Mohammed al-Bukhaiti, a senior Houthi official, told Russia’s Izvestia newspaper that Russian and Chinese ships faced “no threat whatsoever” in the Red Sea, emphasizing that “free navigation plays a significant role for our country”, just for nations not aligned with Israel or its key allies.

In light of this, America’s past lack of interest seems rather foolish.

The West

Many who look at the bluster from Mar-a-Lago about annexing the Panama Canal, Canada or Greenland see a streak of madness, but the underlying approach is rather clear. The areas of focus are maritime chokepoints, lines of communication across the great trade routes of the world.

The communication style leaves much to be desired, but the confusion it is causing is parhaps an advantage. When he wanted to build Trump Tower, he was repeatedly turned down by Tiffany & Co. for the rights build into the airspace above, which were owned by Tiffany’s. Trump then negotiated directly with Tiffany’s leadership, by asking his architect to prepare two plans, one for the most beautiful building possible (tastes may vary), and one for the most ugly building he could conceive within his rights. After an initial rejection, Tiffany’s chose to let him build, lest he ruin the aesthetic of the neighbourhood out of spite.

The seeming absurdity of the annexation claims obscure deeper strategic aims regarding key shipping routes, and the likelihood is that unless the relevant parties give America the trade guarantees it seeks, they may lose their sovereignty outright.

This may not necessarily be a case of a direct takeover though. Broadly speaking, America is looking to foist more of the burden of global security onto its former vassal states conquered in WWII - Europe, Britain (and its former Dominions) and Japan.

But the aim is clearly focused on developing meaningful security guarantees. The Europeans are characteristically slow-moving, melancholy and irritable, but the Japanese have been enthusiastic.

Japan’s Free and Open Indo-Pacific (FOIP) policy includes state and private enterprises, to preserve freedom of navigation in the Indian and Pacific Oceans, against both Chinese expansion and Middle East/North African piracy. The need for outward-looking strategy was highlighted by the Red Sea crisis, where Houthi rebels seized a Japanese-operated ship, with no support apparent from the US, due to the indecision in the previous administration.

The FOIP brands itself as an arm of the Liberal International Order, allowing Japan to regrow their naval muscle while preserving harmonious relations with their allies. Cambodia, Vietnam, and the Philippines increasingly host Japanese naval vessels, as does Kenya and India.

Britain itself could benefit from pursuing just such a plan, but finds itself under the possession of the luminaries of the Fabian Society, distracted by self-mutilating left-wing attitudes and weighed down by a decaying authoritarian malaise and general crisis of institutional competence.

It has retreated, not just from its imperial high-water mark, but even from the reduced significance it enjoyed in the postwar period. The Royal Navy is a diminished force, strained by shrinking numbers, poor readiness, dwindling recruitment, and inadequate funding. Defence Secretary Ben Wallace argued in 2023 that the Navy needed £11Bn just to sustain the existing fleet, but was only given £5Bn.

They struggle with recruiting, having achieved only 60% of their target (2 436 of a desired 4 060), losing 74,000 applicants to delays. By late 2024, Navy Lookout reported the frigate count dropped to 8 after HMS Westminster, HMS Argyll, and HMS Northumberland were retired (confirmed November 2024), leaving 8 Type 23 frigates and 6 Type 45 destroyers (14 total surface combatants). Submarines remain at 6 (5 Astute-class, 1 Trafalgar-class), with only 90 days at sea combined in 2024. The 2 aircraft carriers persist, with HMS Queen Elizabeth and HMS Prince of Wales alternating operational status due to sharing spare parts.

It is not as if the UK government are not aware of the general problem. The defence budget rose from 2.1% of GDP in 2023 (in line with NATO targets) to 2.3% of GDP 2024-25 with plans to reach 2.5% by 2030.

But instead of leaning into its strengths, incumbent leaders are doing the opposite. Recent efforts to hand over the Chagos Islands (of the “British Indian Ocean Territory”) to Mauritius, and to pay the Mauritians heftily to take them, run contrary to the wishes of both the indigenes (forcibly removed 1968-73) and the United States, who share a joint military facility on the islands. This has been criticised from almost every angle.

Currently, Starmer is planning to send troops to fight on the ground with Russia, disrupting peace talks with the United States. Russia, which regards this as unacceptable, seems nonetheless unintimidated. At fewer than 80 000 personnel and falling, and a £3.9 billion deficit in the Ministry of Defence’s (MoD) equipment plan, recruitment and equipment shortages bode ill for this adventure.

It is widely remarked on that the UK is not prepared for the expense, and the much spoken-of option of a military draft could also prove disruptive at home. Labour’s popularity has plummeted since its election on a mere 33.7% of the popular vote; voting intentions have fallen to just 24%. The state is increasingly seen as draconian, exceeding even Russia in its arrest figures for speech violations.

A sensible government which succeeds Labour could focus efforts on Britain’s traditional strengths at sea, instead of focusing on a brutal and so-far fruitless land war.

A Free and Open Atlantic

In order to turn this situation around, the UK needs a military strategy that compliments the broader Western order, and that means establishing a maritime sphere of influence of sufficient size to make an impact, but limited enough to be realistic.

Practically, this means the South Atlantic. British naval presence here is centred on protecting the Overseas Territories, with a permanent garrison at RAF Mount Pleasant in the Falklands, the Ascension Island Auxiliary Field, and a few submarine patrols. King Edward Point on the island of South Georgia, now run by the British Antarctic Survey, could be recommissioned.

But these are incomplete while the Cape of Good Hope remains open. The Atlantic is a broad region to patrol, compared to the narrow area of safe passage around the Cape, which provides access to the Indian Ocean, and Australian shipping.

While it doesn’t appear on the face of it to be a “choke point”, the relatively narrow channel available for commercial shipping makes it vital to avoid the aggressive winds and swells in the southern oceans, and the safe shipping lanes fall entirely within the South African economic exclusion zone (EEZ).

The map below shows a heat map of shipping traffic - the redder the colour, the more traffic. The grid shows our EEZ.

During the Red Sea crisis, sea traffic around the Cape of Good Hope saw daily vessel passages rise from an average of 40 in early 2023 to 85 by late January 2024, and a 75% increase in trade volume. As Western Suez transits drop to a trickle, Russian and Chinese vessels continue using the Red Sea route unhindered.

Ultra-large container ships almost exclusively use this longer path. Yet they decline to refuel or refit in South Africa, due to the terrible quality of its ports, ranked least efficient in the world in the latest World Bank report, along with other South African ports.

The navigable passage around the Cape is bounded by the Agulhas Bank, a continental shelf extending approximately 250 km (135 nautical miles) south of the coast, with depths shallowing to less than 200 meters.

Surface wave heights average 3-5 meters annually, with 10-15% of days exceeding 6 meters. Extreme events produce rogue waves, statistically occurring at a rate of 1-2 per 24-hour period in the region, with recorded heights up to 34 meters. Wind speeds frequently exceed 20 m/s, with gusts reaching 30-40 m/s during winter storms (June-August), per ECMWF reanalysis.

Famously, the SS Waratah, a 9,333 GRT passenger-cargo steamer, sank off the Cape of Good Hope in 1909 during a voyage from Durban to Cape Town, after it encountered a severe storm with winds exceeding 25 m/s and wave heights averaging 8-10 m, per survivor accounts from the nearby Guelph. No wreckage or 211 souls were recovered.

Safe transit is confined to a corridor roughly 50-70 nautical miles wide.

The confluence of the Benguela Current and the Agulhas Current generates significant hydrodynamic instability. Submarines find it far easier to hide from sonar in South African waters, because of the complex mixing of warm and cold water layers, which sonar can’t cross. In 2007, a single South African submarine, the SAS Manthatisi, successfully evaded NATO’s wargame search party, and “sank” every ship partaking in the exercise.

The rocky coastline, including submerged reefs like Bellows Rock, lies within 5-10 nautical miles of primary shipping lanes. Historical wreck data from the South African Maritime Safety Authority indicates over 3,000 incidents since 1500, with 50-60 modern-era groundings or collisions (1970-2020) due to weather or human error. Radar and sonar clutter from wave action reduces detection reliability by ~20-30% in storms. The passage’s remoteness limits rapid response. Satellite coverage provides ~80-90% real-time tracking, but subsurface threats exploit thermocline depths (100-200 m) and current noise for concealment.

Comparing maritime chokepoints around the world with traffic above 10,000 annual transits, the Cape comes up first in the world in accident rates for the above reasons.

The Cape imposes a 7-10 day detour versus the Suez Canal for Europe-Asia routes, but with the Suez falling to Eastern control, South Africa should be looming big on anyone’s radar.

In WWII, sea traffic increased after the fall of Hong Kong and Singapore, and the . Ship visits to the Cape rose from 1,784 in 1939 to 2,593 in 1943, and from 1,534 to 1,930 at Durban. Naval visits rose from 10 to 306 in Cape Town, and from 16 to 313 in Durban over the same period. South African produce supplied to ships rose in value by a factor of 38 between 1939-45. German submarines alone sank 110 allied and commercial vessels outside the Cape Town port during the two years between 1941 and 1943.

The Cape was a major focal point for Cold War security too, and the UK signed the Simonstown Agreement in 1955, which retained Royal Navy rights to Simonstown’s facilities in Cape Town, including docks and repair yards, and defence collaboration over the sea route.

But during the Falklands War, South Africa was under embargo, and the Simonstown Agreement was null, so they refused to assist. This meant launching the defensive operation from Ascension Island, roughly halfway between the UK and the Falklands (6 300 km from the UK and 6 400 km from the Falklands), a two week trip on each leg.

Ascension Island had a small harbor with minimal docking capacity, forcing much of the resupply and troop transfer to occur via ship-to-ship operations or helicopter lifts. Wideawake Airfield, the island’s key airstrip, was a critical asset, but its single runway and limited apron space constrained the volume of aircraft operations.

The Task Force required enormous amounts of fuel, food, ammunition. Everything had to be flown in from the UK (via RAF airbridge) or shipped across the Atlantic.

Ascension was a cramped, volcanic island with little infrastructure beyond the airfield and a small settlement. Thousands of troops, including 3 Commando Brigade and 5 Infantry Brigade, had to be marshalled, reorganized, and loaded onto ships like the QE2 and Canberra under tight conditions, often sleeping in tents or on decks while awaiting transit.

Simonstown would have meant a week less travel time to the Falklands, ready access to landed supplies, ample landing space for aircraft, and ample accommodation for troops. This is not simply cutting supply lines in half, but reducing them by 3/4s, as Ascension Island had to be supplied at the back end by the UK, whereas Simonstown has a continental economy behind it.

Failure to grasp the seriousness of the Cape leaves the implication that South Africa, which is closely tied to China for ideological and economic reasons, could assist Eastern powers in gaining backdoor access to the Atlantic, and shutting off both Suez and the Cape would cripple Europe and Australia.

The ANC already sends its cadres to train in China, hosts special Chinese-overseen police stations which prioritise Chinese settlers and speak to them in Mandarin, financed and built an entire colonial mining settlement (or “Special Economic Zone”) in Limpopo, and votes with them in all matters in the UN General Assembly.

The current diplomatic spat between South Africa and the United States could see something dramatic emerge if the strategic dimensions are grasped.

Opportunity

South Africa has two major vulnerabilities here.

First is the Cape independence movement. While small and underfunded, they benefit from a broad positive sentiment among the general population. Most in the Western Cape recognise their lives would be improved by secession, even if they are too scared of the ANC to try vote for anyone besides the DA.

What’s more, the terrible state of our ports means that we simply cannot afford to turn down any assistance offered to refurbish and expand them. Even if the Americans and the British cannot see themselves backing secession, they can certainly try other deals to secure future port access.

Efforts to arrest the decline of local ports have been marginal, piecemeal, and underwhelming. With little ability to attract FDI, and a straining national budget, South Africa can’t afford to turn down help. The first partner to make a deal (e.g., bolstering ship repair capability or dry dock construction) could establish a meaningful foothold.

This would also offer leverage over South Africa’s less wise decisions, such as the nuclear power deal with Russia and Iran. With rumours that China is contemplating a military base in South Africa, the time may soon be coming when one side or the other makes their move.

Despite South Africa’s partisan stance in international relations, the Western Cape province is decidedly pro-Western in its orientation, and increasingly autonomous. With a nascent separatist movement in the wings, there may be opportunity for a more creative approach if Pretoria proves hostile.

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