The last pirates to be hanged at Execution Dock in Wapping in 1830 marked the twilight of an era of piracy that the Royal Navy had largely brought to an end by the mid 19th century by the use of steam gunboats. Once it became apparent that the chances of intercepting pirates at sea was small, and the navy couldn't afford to detach large parts of the fleet for convoy duties, they resorted to the expedient of sending shallow-draft steam gunboats that could work against wind and tide into the lairs of the pirates and then burning and destroying the vessels, stores and buildings they found there. A pirate without a ship is just a mugger. Now it seems we must learn this lesson all over again.
A decade ago piracy was largely confined to the South China Sea. Now it threatens our lifeline through the Suez - and remember that half our food is imported by sea, never mind the container ships packed with iPods and plastic Christmas trees. On the North African coast, too, the pirates are re-emerging, for the Straits of Gibraltar are just as attractive a pinchpoint as the Gulf of Aden. Now they're smuggling Africans into Europe, but it won't be long before the first ship is seized here.
The Times is quite right in its leader this morning. New threats mean new rules of engagement. Or rather old threats mean rediscovering the old rules of engagement. Somali or Algerian ports and harbours that shelter pirates, their ships and stores must not be immune to robust naval action on grounds of sovereignty.