Defence cutbacks and overseas operations mean there is not a single warship on standby in the British Isles to call into action in the event of a terrorist attack.
Why I harbour doubts about British naval strategy
During a visit back to the UK last month I took a boat trip around Portsmouth Harbour, a body of water with more history submerged in its sediment than many nations could hope to dredge up from their entire past.
There in the historic dockyard can be seen the power and the glory of Britannia's wave-ruling past, represented most impressively by HMS Victory, the flagship upon which Admiral Nelson met his end at the Battle of Trafalgar in 1805, and the remains of the Tudor warship the Mary Rose, lost off Portsmouth while seeing off a superior French fleet on July 19, 1545.
Normally, a collection of grey warships serves as a reminder that Portsmouth remains the home of the British navy, as it has been since 1194. But as we messed about in our jolly boat the only grey in sight was courtesy of the October clouds scudding over Southsea Castle, from which Henry VIII had watched the Mary Rose sink.
This week, the absence of ships was explained by an article in The Telegraph, under the headline "No warships left defending Britain after Defence cutbacks". The Royal Navy normally has at least one frigate or destroyer standing by - the Fleet Ready Escort - to respond to any potential threats in home waters. However, reported the paper, defence cuts and the war in Libya "meant there hasn't been a vessel available since the start of October". And that, for an island nation, is a sobering thought, which in times past would have quickened the pulse of assorted enemies, notably the French, Spanish and Germans. Today, we are all the best of friends, but Portsmouth's forts, memorials and Luftwaffe town-planning are a reminder that history is a long game, during which allies frequently change sides.
Once, Britain had the world's most powerful fleet, a force upon which, for better or worse, the British Empire was built. Now, strapped for cash, the Royal Navy is down to a bathtub-sized fleet of fewer than 20 frigates and destroyers.
Britain owes much to its navy - its very existence, perhaps, and much of its vocabulary; loose canon, close-quarters, the bitter end, in the offing, cut and run, etc. Sentiment, of course, is no reason to resist change, but even if Britain is unlikely to see a modern-day Armada ghosting up the Channel, having at least one warship on guard seems like a good idea. So thought former First Sea Lord Admiral Sir Alan West, alarmed at the absence of the Fleet Ready Escort. "If there was a terrorism incident in UK waters, this would historically be the ship sent in to deal with it," he told The Telegraph.
Following the government's strategic defence review last year, all three branches of the military are undergoing deep cuts; by 2015 some 22,000 jobs will have been lost, mainly from the army, which will shrink to its smallest size since the Boer War. The navy and the Royal Air Force will each lose 5,000 personnel.
When the axe fell on the first 1,000 navy jobs in September, the Ministry of Defence could barely conceal its disgust. It was "not possible for the navy to reduce in size without including many individuals who have regularly contributed to operations throughout their careers". Indeed, "a large number of Royal Navy and Royal Marines personnel are today engaged in operations ... in Afghanistan and off the coast of Libya, for example."
In these financially straitened times, it could be argued that defence, like charity, should begin at home, but the short-termist priority of the defence review is "to ensure that our mission in Afghanistan is protected".
Which explains why, should Nelson's ghost still pace the quarterdeck of the Victory in Portsmouth, he might be heard to echo sadly the words he famously spoke before turning a blind eye to orders and destroying the Danish fleet at the Battle of Copenhagen in 1801: "I see no ships."