Twitter was alive last night with messages from the panic-stricken, warning of ISIS's march on the ancient city of Palmyra, Syria: the latest UNESCO World Heritage Site to be threatened. The potential destruction of this precious two thousand year-old city is being described as 'a human catastrophe'.
'If they enter the city,' warned a spokesman, 'it will mean the destruction of temples, ruins, tombs.'

We have seen already the demolition of archaeological sites in neighbouring Iraq, including those at Mosul, Nimrud and Hatra. Islamic State are said to believe that ancient relics promote idolatry, and must be obliterated. UN Secretary General Ban Ki Moon denounced the attacks as 'a war crime.' Others have warned that it heralds the 'destruction of civilisation'.

I sometimes think it incredible that any man-made constructions from the ancient world have survived. I've seen the pyramids at Giza, and the Sphinx. The temples at Karnak, and Tutankhamun's tomb. The cracked, crumbling relics in the Cairo museum are disintegrating by the day, because the conditions in which they are kept deny long-term preservation. In Athens, the Parthenon shakes, but is not a priority.  We were right not to hand back the Elgin Marbles. Where would they be now? Rome's Colosseum, meanwhile, and other Eternal City monuments, are said to be next on the hit-list.

On a British Council tour of Syria, Iraq and Jordan years ago, with a band from Newcastle called Hurrah!, our party visited the ruins of Babylon, where the legendary Hanging Gardens are less than a memory. We hung out in Baghdad. We cavorted for the camera at the Arc of Triumph. Rode donkeys into Petra, the 'rose-red city half as old as time'. Such a casual 'cultural' expedition would be unthinkable now.

Most of the original Seven Wonders of the Ancient World - the aforementioned Hanging Gardens, Olympia's statue of Zeus, Artemis's Temple at Ephesus, the Halicarnassus Mausoleum, the Colossus of Rhodes, the Lighthouse of Alexandria - are now dust in the sands. Only Egypt's Great Pyramid from the classic list of Wonders remains. It is widely assumed that those Wonders existed simultaneously. You would have needed a Tardis to see them all at once. A
ll that remain of them are mouldering etchings. There was no digital technology back then.

Meanwhile, the Great Wall snakes across China, not quite visible from outer space, as has been claimed. Venice wobbles. Stonehenge stands strong while Everest shakes, the antique culture of Nepal destroyed in a beat.

All ancient sites suffer the effects of war and weather, geology and nature, pillaging and looting, neglect and time.They will all, eventually, be nothing. At least we have photos and film. We will always know that they were there, and what humankind is capable of.

Isn't it the point? Humankind? People? While the loss of monuments can be terrible, it's not tragic. Who is doing the headcount, keeping score of the executions? Sad though monumental destruction may be, how can it supersede murder and barbarism? 

I have a ticket stuck to the wall above my desk, from the last time I stood on the observation deck of New York's World Trade Center, not long before before 9/11. Those edifices and their satellites are gone. Others have replaced them. The ghosts of the thousands who perished remain the tragedy.