Flame and smoke rise from Crimean Bridge connecting the Russian mainland and the Crimean peninsula over the Kerch Strait. Photo / AP
Just before dawn on Saturday morning, a security camera filmed two lorries and two cars driving west on the Crimea road bridge.
In an instant, the screen went white. When the curtain of flame receded the lead vehicles had vanished, the road bridge was in the sea, and a train on the neighbouring rail crossing was ablaze.
At least three people - the driver of the lorry and two people in the car overtaking it - were instantly killed, Russian investigators said.
By mid-morning clip-board wielding officials from the Russian investigative committee were on the scene to inspect the damage. But it is still too early to say how the Kerch bridge was blown up.
Was it an improbably - perhaps impossibly - daring commando raid? A missile of longer range than the Ukrainians are known to possess? Or, as Russian investigators initially said, a truck bomb? Some propagandists hinted at a suicide bomber, something unheard of in this war.
In a way, the method is irrelevant. No matter how you slice it, this is a bitter blow to the Kremlin.
The destruction of the Kerch bridge has been a fantasy of pro-Ukrainian social media trolls - and the nightmare of their Russian counterparts - since the beginning of the war.
The Ukrainian post office immediately unveiled a stamp showing explosions on the bridge as a follow-up to its earlier one commemorating the sinking of the cruiser Moskva.
Mikhailo Podolyak, an advisor to president Zelensky, mischievously suggested the Russian military had blown up the bridge in order to discredit the FSB, who are responsible for guarding it. Some people seemed to take his trolling seriously.
Other Ukrainian officials did not explicitly take responsibility but posted enough mocking social media memes to make clear they wanted the world to believe they did it.
On the other side of the information war Alexander Kots, a hawkish Russian war correspondent, wrote despairingly that the "most stupid thing to do now would be to reassure the country nothing bad happened. It did."
He was among several prominent war commentators and propagandists to demand Russia stop showing restraint on the battlefield in revenge for this "act of terrorism."
sick burn
— Ukraine / Україна (@Ukraine) October 8, 2022
Igor Strelkov Girkin, a Russian intelligence officer turned nationalist blogger who predicted a Ukrainian strike on the bridge in August, seemed happier to have been proved right than dismayed by the consequences. "I didn't think I'd predict it to the very week," he wrote with false modesty.
Ukrainian officials have long made clear they consider the Kerch bridge as a legitimate target, and Russian officials have staged defensive exercises, including covering it in a smoke screen.
But until now an attack on it seemed unthinkable - for both practical and political reasons.
Practically, because blowing up a bridge is at the best of times extremely difficult.
The Kerch strait lies at least 305km from the nearest Ukrainian-controlled territory - putting it out of range of nearly all the heavy ordnance Kyiv is known to possess.
It was heavily defended by air defence missile systems, making a potential airstrike a kamikaze mission.
The maritime approaches on both the Azov and the Black Sea sides of the strait are tightly controlled by the Russian surface fleet.
The waves beneath are supposedly patrolled by killer dolphins specially trained to hunt down enemy frogmen.
Only 3 months ago, Russian propaganda was claiming that the Crimea bridge was impossible to attack because of 20 different modes of protection covering it, including military dolphins (#17) https://t.co/gJdON9o4Vl What a colossal failure pic.twitter.com/70ZrQoKXYb
— Elizabeth Tsurkov🌻 (@Elizrael) October 8, 2022
Tight security at either end should have prevented anyone from attacking by land. It should have been the hardest of targets.
Politically, although Ukraine has always reserved the right to hit anything in Crimea, the bridge was always tacitly understood to be a Russian red line that if crossed would provoke a devastating response.
That is because the 19km bridge is more than a mere logistical bottleneck.
It is also a symbol of Putin's personal power, of modern Russia's ability to build like the Soviet Union, and of the permanence of the 2014 annexation of Crimea.
The Romans built triumphal arches for their conquests. Putin built a bridge.
It is the longest bridge in Europe and an impressive engineering feat.
The strait of Kerch, although narrow, is notorious for sudden and violent storms. The underlying geology is also treacherous - the Taman peninsula on the Russian side is famed for its unstable mud volcanoes.
But since the 19th century, many have dreamed of bridging the gap.
The last time it was seriously attempted was during the Second World War, when the Wehrmacht tried building a crossing to supply the Nazi thrust into the Caucasus.
The Red Army recaptured the area and finished the job with a temporary pontoon structure, but it was soon destroyed by drifting ice.
The job was so difficult - and fraught with Western sanctions - that Putin initially struggled to find private-sector investors when he ordered the construction in 2014.
Eventually, he entrusted it to Arkady Rotenberg, his former judo partner and a billionaire construction magnate already under sanctions.
In 2017, the Telegraph visited the site at the invitation of Stroygazmontazh, the group doing the building.
It was impossible not to be impressed by the scale of the project.
Taman, a dusty and neglected fishing town, had been transformed by a small city of shipping containers housing hundreds of workers.
Earthmovers and equipment moved back and forth along a grand causeway to the island of Tuzla. From the end of the causeway, the cliffs of Crimea looked close enough to swim to.
Managers at the time brushed off questions about delays and insisted they would get the $3.6 billion ($7.12 bn) job done on time.
To be fair to them, they delivered.
So famed is the bridge in Russia that it inspired the 2018 Russian romantic comedy "The Crimean Bridge, Made with Love!" made by the head of the Russian network RT, Margarita Simonyan.
Vladimir Putin drove the first truck across the road section in a televised opening ceremony in 2018.
Its destruction presents the Kremlin with two urgent challenges.
First, there are immediate practical issues.
Until the bridge can be repaired, freight and passengers headed to and from Crimea will have to be re-routed by air, sea, and the "land bridge" of occupied Ukrainian territory along the north coast of the Sea of Azov.
That is bad news not only for the Russian war effort. The highly-militarised peninsula was one of the springboards for the February 24 invasion and remained a key supply route for the Russians fighting on the southern front.
Less than two months ago, reinforcements were rushed through Crimea to reinforce Kherson ahead of the Ukrainian offensive there. The force trying to hold back the Ukrainians there still relies on that route for resupply.
There are also around two million civilian residents who need feeding. There were already reports of long queues forming at supermarkets as locals stocked up in anticipation of shortages.
Those difficulties are surmountable.
Russia's transport ministry said trains would be running by evening, and that the surviving eastbound lane of the road bridge would also be reopened for traffic in both directions.
But the vulnerability of those supply chains has been exposed.
Such a public blow to Putin's prestige demands a public response.
He will be under pressure to do something dramatic to assuage both the shaken general public and the vocal, hard-line minority of war enthusiasts he increasingly relies on.
Ukrainian officials - and their allies in Western capitals - will be bracing for something violent.
He could try to strike Ukrainian bridges across the Dniepr river in Kyiv, Dnipro and Zaporizhzhia, or just launch mass bombardments of such cities.
He may even launch the much debated demonstrative nuclear strike - or at least carry out an explosion at the old Soviet testing ground on Novaya Zemlya in the Arctic.
The difficulty is that this is not an isolated setback. It comes after a month of defeats and retreats in Kharkiv, Liman, and Kherson that have already shaken faith in victory.
Bridges can be repaired. The widening cracks in Russian morale are another story.
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