As a grim dawn broke over Berlin, Germany struggled to understand what had happened hours earlier at the capital's Breitscheidplatz Christmas market.
One minute a cheery oasis in the grey Berlin winter, a place of blinking lights, cheesy music and mulled wine. The next a place of screams, death and silence as a black articulated lorry sliced through the wooden huts and crushed market-goers before juddering to a halt at a Christmas tree.
A dozen dead, nearly 50 injured and more questions than answers as a weak sun rose over the freezing German capital.
The Kaiser Wilhelm Memorial church, the jagged outline of its ruined tower a permanent memorial to a terrible war and a hard-won peace, this morning has another memory of senseless death and destruction to bear in the most vulnerable of places: The German christmas market.
This morning, even before the identities of the dead were known, pastors in the Lutheran church will open a book of condolence in the octagonal, post-war church. Across town, city officials will attend an ecumenical mass
Outside on the pavement of the Breitscheidplatz, a handful of carnations and a few flickering candles marked the spot where the Scania truck with a Polish registration left the road and ploughed its way into the market, less crowded on a Monday night than at weekends.
During the night, deathly calm reigned in what is usually one of Berlin’s most busy intersections. Investigators in white plastic overalls erected white barriers to block inquisitive gazes while, nearby, others quizzed a man apprehended two kilometres from the scene and believed to be the truck driver.
A second man - dead in the passenger seat behind the truck’s ruined, punctured windscreen - was a Polish citizen.
Was this a copy of the July 14th attack in Nice? Or the act of a lone, crazed man? Was the suspect an Afghan or a Syrian? A petty thief or a radicalised Islamist?
As rumours swirled, there was only one certainty this morning: after a series of lucky escapes, Germans now fear the worst.
One Berliner in particular woke with a feeling of dread at the hours and days ahead. Chancellor Angela Merkel knew this day would come eventually; her security analysts said a large-scale attack was impossible to prevent.
Now it is here, the German leader faces the most difficult hours of her 11-year political term if the perpetrator is confirmed as an asylum seeker.
Dr Merkel will need all her skill to forge a calm course: offering comfort while urging caution, acknowledging public insecurity towards a refugee policy she sanctioned while insisting the hateful acts of an individual cannot condemn a an entire group.
But in these hours of fear and uncertainty, as police step up patrols on beloved Christmas markets all over the counry, all eyes will be on the German leader and her ruling Christian Democratic Union (CDU).
Two weeks ago Dr Merkel bowed to conservative pressure in her party and adopted a tougher line on refugees and deportations. A year after Germany took in nearly one million asylum seekers from Syria, Afghanistan and northern Africa, Dr Merkel accepted that not performing even a partial pivot to the right would exacerbate a voter drift to the far-right ahead of next September's election.
As Germany enters the election cycle, she will come under massive pressure to step up her shift to the right from growing populist forces within her own party.
Also under pressure, Germany’s mainstream media held firm and took a cautious line after the attacks. Almost a year after over 130 sexual assaults at Cologne’s New Year celebrations, many news outlets were attacked for being slow to report how many involved non-nationals and asylum seekers.
On Monday night and Tuesday morning, most outlets resisted the urge to dub this a terrorist attack, or even an Islamist one, and only reported news as they got it from police.
Television and radio urged calm and, in a country where “post-factual” was dubbed word of the year, worked hard to separate fact from fiction. But the media knows, too, that this attack has the potential to trigger something bigger.
After the Cologne attacks and a series of attacks in Bavaria over the summer, all of which had some asylum seeker involvement, a grim year in Germany has ended with another handful of horrifying crimes.
A young Afghan man stands accused of raping and murdering a 19-year-old woman in Freiburg, near the Black Forest. This week Germans were perplexed and horrified by news of a foiled attack on a Christmas market in southwestern Ludwigshafen by a 12-year-old German-Iraqi boy.
A year on from its “welcome culture”, these high-profile incidents have catalysed an already darkening mood towards Germany’s new arrivals and German mainstream politicians torn between whether to challenge the populist pied pipers - or join them.
The fact is that daily attacks on asylum seekers and refugee homes, particularly in Germany’s east, vastly outnumber the number of attacks, assaults and other crimes linked to asylum seekers.
But in the seething social media cesspool, every crime carried out by an asylum seeker or refugee is magnified by many more fictional incidents, meaning Christmas has come early for the far-right Alternative für Deutschland (AfD).
Days after agreeing a programme of "targeted provocation" to maximise support in next September's federal elections, senior AfD figure Marcus Pretzell wasted no time putting theory into practice on Monday night.
Just an hour after the attacks, he posted a tweet insisting these were “Merkel’s dead” - and was promptly told by others to “shut your brown mouth”.
When Dr Merkel goes before the cameras today - a disturbed public listening, a new wave of populists poised - her already complicated fourth-term election bid next year has now become considerably more difficult.