The phrase ‘ring of steel’ hardly begins to describe the operation here in Calvados country as we await the 70th anniversary of the pivotal moment in modern history. Some world leaders are bringing warships as well as jets to the D-Day commemorations. The exclusion zone not only covers a chunk of northern France but even extends to cross-Channel ferries. Every Normandy veteran has had to be cleared for a pass although, as many point out: ‘We didn’t need a pass on 6 June 1944.’

If the cops are nervous, the protocol people are beside themselves: what do they do with President Putin? He may be the pariah du jour but Russia, which lost 27 million to Nazism, has to be included. Now that Putin’s been booted out of the G8 after annexing Crimea and his Winter Olympics are over, this is his one opportunity to grandstand with the head-of-state club. The crunch point will be Friday’s team photo and cosy lunch at the Château de Bénouville. Since D-Day was chiefly a UK/Canadian/US affair, the Queen and President Obama will be at top table with President Hollande (Prince Charles and David Cameron, not being heads of state, will be elsewhere). But if the French place Putin too far below the salt, the new Cold War may turn glacial.

This anniversary has a record of political tension. Come the 50th, in 1994, there was an EU schism when the Germans were not invited. At the 60th, the veterans complained when they were. At the 65th, President Sarkozy invited President Obama but not the Queen, and Gordon Brown was booed. The 70th bodes well for Angela Merkel, though. It will be a pleasant change for a German Chancellor to be in Normandy and see someone else on the naughty step.

Mr Hollande has another one for ‘Dear Mary’. The Queen and the Duke of Edinburgh are making a state visit to Paris this week. Yet France, famously, has no first lady to share the load and look after the Duke. Mr Sarkozy had a similar problem ahead of his 2008 state visit to Windsor. With a few weeks to go, he married Carla Bruni.

There’s much talk of this being the ‘last hurrah’ for the D-Day warriors. They’ve heard it all before. Five years ago, the officers of the Normandy Veterans Association called it a day, whereupon a splinter group set it up all over again. Some 650 members of what might be called the Continuity NVA are here this week. They will curtail national operations after this anniversary but carry on at branch level. Several tell me that they’re already looking forward to next year — when the heads of state are not here and the traffic is back to normal.

Among the toughest of D-Day missions was the Parachute Regiment’s night assault on the German guns at Merville. Stuart Tootal’s book All Manner of Men deftly captures the agonising way in which everything went wrong. Yet with just 150 men from an original force of 750, they pulled it off. It was a famous feat of arms. Less well-known is their heroism afterwards as they spent a week dug in around the Château Saint-Come fighting off Rommel’s infantry, artillery and Panzers. It reads like Rorke’s Drift. A battalion that left Britain in 32 Dakotas and three Horsa gliders came home in four trucks. Gordon Newton is among the veterans of 9 Para in Merville this week for the unveiling of a new memorial. They had been expecting their regimental colonel but officialdom messed up and Prince Charles has to lay wreaths elsewhere. The veterans are stoical, less so the people of Merville. Like so many Normans, they are fiercely protective of ‘their’ old boys. ‘We just feel lucky to be alive,’ says Gordon, who went on to a distinguished career in the Met. ‘But the mayor’s taken it very badly.’

These events remind us what we lost when Tony Blair pensioned off the Royal Yacht to a cruise terminal in Leith. On the eve of the 50th anniversary of D-Day, a million lined the Solent to wave her off to Normandy with the Queen and the leaders of the free world aboard. I well remember Lech Walesa of Poland, pressed to the deck rail, fists clenched and speechless with emotion, while Bill Clinton surveyed the scene and quoted Eisenhower. Since national pride dictated that he should land in a US vessel, Mr Clinton had to jump ship — literally — south of the Isle of Wight and nearly fell in. Come nightfall, Britannia steamed up the canal to Caen. At Pegasus Bridge, she was greeted by bands, saluting veterans and sobbing crowds. This week, the Queen and Prince Philip arrive on a scheduled Eurostar service.

Normandy’s cemeteries are looking sublime. The biggest — and gloomiest — is the German one at La Cambe. Here lies the tank ace Michael Wittmann. As James Holland’s fine BBC documentary, Normandy ’44, reminds us, Wittmann once destroyed 29 British tanks and personnel carriers here in just 15 minutes. Among the many flowers on his grave is a British Legion cross.