The Cromwell Strategy

Oceans are now battlefields. It is as true today as it was during the Napoleonic Era. But instead of seeing a great power assert its dominance over the world’s oceans, we are witnessing the global retreat of a great power. The Iran War is the latest step towards the end of Pax Americana and the return of spheres of influence. American power has kept the world’s sea lanes open for almost a century. Before that it was the Royal Navy that ruled the waves. With no great power ready to take the place of the United States, we are reverting to the geopolitical situation before the advent of British naval superiority in the eighteenth century.

In other words, we will not be going back to the status quo, no matter any statements to the contrary. Iran has no intention of giving up its chokehold over the Strait of Hormuz. This changes the game in more ways than one. Despite a successful decapitation and bombing campaign, the regime can still survive by keeping control over a critical waterway. Air superiority matters but it cannot control the seas. Other powers and non-state actors have now seen how shipping can be weaponised to cheaply hold the global economy for ransom as a means of ensuring their survival or securing concessions from the powerful. China has already spent the better part of a decade muscling in on the South China Sea and the Strait of Taiwan.

Geopolitical competition over global sea lanes is sending us back to another era. There have been many times in history when global sea lanes were unsafe or contested, as was the case during the First and Second World Wars. But this happened during the transition from British to American naval dominance. Chinese naval power, while impressive and growing, is some distance from establishing Pax Sina over the world’s oceans. What we see emerging is a far more fragmented world divided by spheres of influence between multiple great powers. This return to chaotic, unpredictable geopolitics represents a return to the situation when no single power could clearly control or protect sea lanes.

Clear and free shipping lanes can no longer be guaranteed. Even with a rapid programme of reindustrialisation and reshoring, Britain will continue to rely on increasingly vulnerable global supply chains. What should British strategy in a world of increasing dangers and limited industrial capacity look like? Thankfully we have the historic example of England’s most famous strongman to guide us. When Oliver Cromwell came to power a few years after the regicide of Charles I, his primary foreign policy goal was to secure the safety of England’s republican regime. This was in an age during which Britannia did not rule the waves, but the naval struggles of the 1650s show how Britain can advance its interests even when lawlessness prevails.

Shipbuilding For Multipolarity

What makes this period especially relevant to Britain in the 2020s is the prevalence of multipolar competition and non-state actors in naval theatres. England deployed and was threatened by pirates and privateers throughout the seventeenth century. There were sprawling networks of European privateers operating across England’s home waters, the Mediterranean, and the Atlantic. Closest to England’s shores were the Irish rebels, still loyal to the royalist cause, English royalists under the command of Prince Rupert, and English privateers committed to Parliament. Dunkirk and Flemish ports, such as Ostend, provided reliable bases for English and Irish royalist privateers. Prince Rupert launched attacks on merchant shipping, including the grain supply to London, from his base in Portugal until the English navy blockaded the country and forced the Portuguese to recognise the republican regime.

The negative impact of privateering was enormous. Irish attacks on English fishing fleets also drove the cost of insurance upwards, putting additional costs on businesses and deterring investment. French forces sunk or took eight ships, valued at £300,000, from the Levant Company in 1649 in the Mediterranean. Flemish privateers with support from Spain hindered English commerce with 82 licenced privateers capturing 150 English ships in 1656. As many as 2,000 merchant ships could have been lost through the course of these raids.

There has been a similar proliferation of privateers and piracy at sea since the 2010s. Somali pirates in the Gulf of Aden used satellite phones, speedboats, and grappling hooks to locate and hijack ships and take hostages. At its peak, Somali piracy cost the shipping industry up to $3.3 billion a year. There are now reports of a revival in Somali pirate activity as part of a broader increase, particularly around the Singapore Strait. U.S. military operations against the Houthis in the Red Sea have cost as much as $4.9 billion. Maritime terror groups like Al-Shabaab pose another threat to global shipping. These non-state actors will be emboldened and spread as states fight over control of shipping lanes in the years ahead.

English policy was highly effective in dealing with this threat. By 1653 Prince Rupert only had one ship left and was no longer a threat. As one historian noted, “Though some privateering continued it was reduced to manageable proportions. Privateers with foreign commanders and polyglot crews were often indistinguishable from pirates apart from the commission they sailed under, and reports of their outrageous behaviour did nothing to help Charles’s cause.”¹ Parliament, and then Cromwell, used naval power to crush Prince Rupert’s forces, bring order to royalist holdouts in the colonies, and gain recognition of the regime from the French, Spanish, and Dutch.

Most relevant to the present moment is the fact that an effective response to the threat of privateers required Parliament to reshape England’s navy. Privateers prioritised their attacks on merchant shipping, rather than men-of-war, as softer and more profitable targets. Under the Stuarts, England had built large warships like the Sovereign of the Seas. But Parliament shifted its efforts towards smaller, faster ships that could protect merchant shipping. This led to new vessels like the Adventure, Assurance, and Tyger during the 1650s.

These were deployed to protect merchant shipping. Convoys began to escort merchant shipping through sensitive areas like the Strait of Gibraltar, led by Edward Hall, Henry Appleton, and Richard Badiley. The English navy also started attacking French shipping in 1650. In 1652 Admiral Robert Blake destroyed a French fleet sent to protect Dunkirk, leading to the eventual formal recognition of republican England by France. By 1658, Dunkirk had been captured and Ostend was blockaded.

This was only possible because of the enhanced power of the state-built navy. The English navy increased by 216 ships in 1649 to 1660. Half were seized from the Dutch as well as Portuguese, French, Spanish and other European powers. A British commander bragged, “We are able to fight them with their own ships.”²

Private Enhancement of State Capacity

In one of Cromwell’s more audacious, and less successful, moves, he put forward a “Western Design” for the expansion of English colonial and naval power in the New World. The strategy was intended to shift the European balance of power in favour of the Protestant states and harmonise relations between them. It also meant reverting to the historic English enmity towards Catholic Spain. Cromwell declared, “your great enemy is the Spaniard. He is a natural enemy.”³ France, while also a longstanding English rival, was not a prime target for plunder due to its lack of colonies and merchant shipping. Spain was a much more promising target for both ideological and commercial reasons.

The starting point would be the Spanish West Indies. As an empire in decline, England hoped to plunder Spain’s colonies and wealth by breaking its trade monopoly in the region, especially regarding gold. Indeed, Cromwell was inspired by Thomas Gage’s The English-American, published in 1648, which recounted the rich opportunities in the New World. One historian has rightly said, “the Commonwealth, with Cromwell as its head, could strive to fulfil the militant Protestant ambitions of piety, plunder, and plantation that had, until then, been accomplished by private citizens and corporations.”⁴

General Robert Venables and Admiral Sir William Penn led the mission to attack the Spanish. The mission began with an attempt in 1654 to seize Hispaniola, now modern-day Haiti and Dominican Republic, but English forces were humiliatingly repulsed and ravaged by dysentery. The force of eighteen ships and 6,000 soldiers was a significant investment that did not pay off. But as a consolation prize, English forces gained Jamaica.

While the formal naval power of the British faltered, the Western Design revealed the potency of private actors. English state power was still generally weak and fragmented, leaving plenty of room for English privateers to participate in this mission. Port Royal in Jamaica was developed and became an entrepôt for privateers of many stripes to flourish.

Cromwell unknowingly facilitated the rise of the infamous Captain Henry Morgan, who arrived in Jamaica as part of the 1655 military expedition. During his career, Morgan defeated Don Alonso’s Spanish fleet after an audacious raid on Gibraltar. Alonso had warned Morgan and his men that they would “perish” if they did not return the stolen booty. But instead of surrendering, Morgan sent a fire-ship loaded with tar and brimstone and “beset with many pieces of Wood dressed up in the shape of men with Hats…and likewise armed with Swords, Muskets, and Bandeleers.” Morgan captured a Spanish ship, sunk another, and seized 15,000 Pieces of Eight for his troubles.

What made Morgan distinctive from being an ordinary pirate was his relationship with the English state. He was working for English interests as a privateer rather than as an outright pirate, though this legal distinction was rarely made in the popular literature of the time. Morgan and his men were certainly not gentlemen, indulging in the worst violence possible. But they were extremely effective and accrued a vast wealth for themselves and damaged England’s rivals. Morgan received a knighthood, a pardon for his crimes, and the post of Deputy Governor of Jamaica. None of this could have happened without Cromwell.

Blake was vital during the ensuing Anglo-Spanish War which erupted in the wake of Cromwell’s attempts to establish the Western Design. His actions against the Barbary pirates and the Spanish forced France and Tunis to make new agreements with England over Mediterranean trade. In 1656 Edward Mountagu negotiated with the pirates at Salé who were more willing to talk after Blake’s actions in the region. Blake also destroyed a Spanish Plate fleet in the Canary Island after the English navy focused its attention closer to European shores. Christopher Myngs attacked Spanish Main and seized plate, silver, coin worth up to £300,000.

A Cromwellian Approach to Naval Affairs

It was Cromwell’s devotion to naval power that put England on its path to greatness. This change was observed at the time. One poet recounted “The sea is your own and now all nations greet / with bending sails each vessel of your fleet / your power extends as far as winds can blow / or swelling sails upon the globe may go.” But the pomp of later centuries overshadowed what Cromwell and Blake had achieved. The royalist historian Lord Clarendon had it right when he said Cromwell’s domestic power was “nothing compared with his greatness abroad.”⁵

The collapse of Pax Americana is giving rise to a new naval competition in which shipping is much more vulnerable, nation states must rely on hard power rather than international law, and non-state actors can pose significant threats to global trade. American firepower can still influence events in chokepoints like the Red Sea and the Strait of Hormuz, but it cannot be everywhere at once. In fact, it is weakening with time. As part of the peace negotiations, Iran is demanding a toll on ships passing through the Strait. Houthis continue to be a persistent threat in Yemen. This is a return to the contested seas of the 1600s with great powers vying for control amidst a range of state and non-state threats.

This earlier era has specific lessons for the present moment. For Britain to protect its supply chains, the most obvious solution is aggressive ship building. This would allow Britain to protect the flow of merchant shipping. But the paradigm must be very different than what has dominated in the last few decades: the threat of a world where critical waterways can be closed cheaply does not mean more aircraft carriers and exquisite munitions. It means smaller, faster vessels that can be manufactured quickly in a cost-effective way and at a massive scale. This is especially vital for a cash strapped country like Britain. These naval forces can be dispatched to trouble areas rapidly or travel as convoys to protect shipping. Autonomous ships should be at the heart of these efforts.

Alongside military ship building, more investment should go into expanding merchant fleets. As proven by the seventeenth century, and modern Chinese practices, merchant marines can serve incredibly useful purposes for the state. Again, smaller, faster, cheaper is better. But these new merchant ships can be deployed in ways to serve state purposes by smuggling goods, transporting special forces, and gathering intelligence. They can also themselves become armed and hire security teams, reflecting the higher level of threat they now face. This is an underused asset in the West that needs to be massively expanded and act as an auxiliary for the Royal Navy.

The legacy of privateering is also important: the practical limitations of shipbuilding in the West impose constraints very similar to the English state of the 1600s. The solution – leveraging private initiative to extend national power – is also applicable here. Britain can develop its own shadow fleet to retaliate against Russian and Chinese sabotage. Letters of marque should be issued to facilitate this, meaning the state can give licences to non-state actors to attack enemy vessels and maritime infrastructure. Private military companies should be authorised to protect merchant shipping and launch attacks on foreign navies with hostile intentions. Large military bureaucracies certainly need reform, and quickly, but enabling non-state forces that are friendly to British interests would be an extremely effective way of delivering immediate results.

Britain, today, resembles its seventeenth century status far more closely than its nineteenth century imperial zenith. It has the long, hard task of rebuilding British hard power and winning back global respect. The spectacle of Russian merchant vessels passing freely through the English Channel, and Russian submarines spying on undersea cables in the Atlantic have exposed Britain’s weakness. Defence spending remains blocked by the Treasury, and human rights lawyers oppose the use of any force that might be construed as a violation of international law. The only beneficiary is the Russian navy. Britain should put aside this folly and embrace a naval strategy that can successfully exploit chokepoints in global sea lanes. This means developing and using the capability to deny Russian access to the English Channel, the GIUK Gap, the Strait of Gibraltar, and the Suez Canal.

This new approach to naval policy would help Britain and its allies to stand up to authoritarian rivals and to hunt down non-state actors who threaten Western shipping, the state of affairs that looks likely to prevail in the coming decades. These problems cannot be solved by international arbitration. Ubiquitous American hard power cannot keep these shipping lanes open or protect the seas anymore. Rival powers are loosening their self-restraint and using every means at their disposal to destabilise the West. This calls for the revival of the Cromwellian drive for hard power at sea among all the nations of the West to hold back these forces and protect our vital interests.

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