And just as important, 44 merchant mariners were rescued by his task force, adding to an already impressive CV that includes chasing down Caribbean drug-runners. There are few who possess greater expertise in protecting the high seas, which is why shipowners’ ears prick-up when Northwood argues that there are increasing risks of attack, from the Suez Canal to the Strait of Gibraltar.

Alongside prostitution, piracy is “one of the two oldest professions in the world”, he says.

A year on from what was said to be the first fair Somali election since 1969, hijackings and similar incidents are now at their lowest level than at any time since they received a $315,000 (£199,000) ransom for the release of the Hong Kong-owned tanker Feisty Gas in 2005. Western business’s perception of the East African nation has mellowed to the extent that the former Conservative Party leader Sir Michael Howard brokered an exploration deal with the new government for Soma Oil and Gas earlier this year. However, Somali bandits patrolling the waters off the Horn of Africa could still be costing the global economy as much as $18bn (£11bn) a year, according to a recent World Bank report.

Mary Harper, the broadcaster and author of Getting Somalia Wrong?, warned at London International Shipping Week this month that the pirates are “just sleeping, waiting for their time to come back”. When she visits the capital, Mogadishu, Ms Harper  is still protected by five bodyguards.

The pirates have also been replaced, for now, by increasing criminality in “pinch-points”, such as West Africa, which has cost shipping companies billions of dollars in altered trade routes, extra fuel costs and insurance. Last month, the Cosco Asia containership was attacked in the Suez Canal by Egyptian militants who were hoping to destabilise the government.

It was the second attack of the summer in the area and al-Furqan, the group claiming responsibility for the foiled attempt on the Cosco Asia, has warned that more will soon follow. “This was a terrorist attack and they are still out there,” Kevin Doherty, the president of US security firm Nexus Consulting, has warned.

Northwood left the Navy at the start of the year, entering the private sector as chief operating officer at Gulf of Aden Group Transits. The Malta-based company has protected more than 40,000 seafarers and is one of the top five maritime security groups that collectively account for around half of the $200m market. 

“If they [terrorists] really want to sink a vessel in the Suez Canal they will learn how to do it; and clearly it is in the Muslim Brotherhood’s interest to keep the canal in difficulties,” Northwood argues. “The attack on the Cosco Asia shows an increased risk, that immediate and sustained, heightened security needs to be implemented on board merchant vessels using the canal, as well as major maritime choke points such as the Strait of Gibraltar and the Bab el-Mandeb Strait [between Yemen and Djibouti].”

The cost of a four-strong team of armed ex-marines protecting a ship on a 10-day voyage across the Indian Ocean comes to about $40,000. A three-person team of two Filipinos and an Estonian team leader come in at closer to $25,000 – either way, these are negligible costs given that the cargo may be worth $100m.

Besides, an armed entourage means that a ship can travel at a more economical pace across the ocean, saving thousands of dollars in fuel costs, rather than attempting to race away from the threat of piracy.

However, taking weapons into ports is not realistic in terms of international diplomacy: “You can’t blame people for not wanting a huge armoury just off their coast,” Northwood points out.

Ports and citadels: seafarer safety

Ships – particularly those carrying refined products that are easy for robbers to sell quickly, such as petroleum – should follow certain basic tactics when entering a port. Many port authorities have been infiltrated by militant and criminal gangs, meaning that they will soon be tipped-off on any lucrative incoming cargo.

Ship masters should inform a port that the vessel is preparing to dock only hours before it arrives, giving gangs less time to prepare. “If you’re getting to port on Tuesday, don’t tell the authorities until Monday evening or even Tuesday morning,” advises Northwood. “Leave it as late as possible.”

Unarmed security advisers can also help seafarers establish citadels (shelters) on the ship and establish quick routes to reach them when under attack.

Security advisers should show crew when they should not be in exposed locations, but being unarmed does not mean that a ship cannot protect itself with razor wire, fire hoses and even decoys, such as mannequins with fake guns to “put doubt” in the attacker’s mind.