Shocking. Unnerving. Unpredictable. Violent. For a decade I have been following the twists and turns of Donald Trump’s America with the privilege of journalistic distance. On Saturday night I felt the darkness come viscerally close.

Bang! Bang! What was that? Where was it? At 8.36pm panic and pandemonium reigned in the cavernous ballroom at the Washington Hilton hotel. There were men running and cries of “Get down!” and “Stay down!”

I saw guests at the White House Correspondents’ Association’s (WHCA) annual dinner – men in tuxedos, women in dresses – diving under the circular tables and I, almost as if acting on a cue, did likewise. It was a scene from a dozen Hollywood movies but now it was happening to me, right here, right now.

Secret Service agents raced through the room, wielding weapons. There was an eerie silence. By the time I rose to look at the dais, Donald and Melania Trump had already been rushed away. Instead, there were four officers with helmets and rifles standing guard against a backdrop of a White House image and the words: “Celebrating the first amendment.”

Then a white-haired man in a tuxedo was led past our table, leaning on two men for support because he could not walk unaided. Who was he? Had he been injured in this drama? We did not know.

How did I feel? It’s a question that reporters ask interviewees all the time. What I felt at that moment was profound confusion and uncertainty. We were in the eye of the storm but had no idea how big the storm was or what it looked like.

This should have been the most secure location in America. The Hilton was fortified after witnessing the attempted assassination of Ronald Reagan 45 years ago. I showed my admission ticket several times and passed through an airport-style metal detector because Trump was attending the WHCA dinner for the first time as president.

Indeed, that meant it was already a highly charged night: would he attack the media on their home turf? Would reporters and other guests applaud him, keep quiet or walk out in protest? Unsettling questions of the Trump era – questions of truth, normalisation, resistance, capitulation, authoritarianism – hovered in the air.

There were some cheers and applause as Trump entered the room to the familiar strains of Hail to the Chief. The president maintained a salute throughout the entire national anthem. Weijia Jiang, president of the WHCA, told him: “It is meaningful that you are here tonight.”

Guests were talking among themselves, eating a spring pea and burrata salad and drinking wine when the rupture happened. We later discovered that an assailant carrying guns and knives rushed a Secret Service checkpoint in a lobby of the hotel before being apprehended. One officer was shot but he was protected by a bulletproof vest.

Minute by minute, a strange calm descended on the ballroom as it became apparent the danger had passed. A metaphor for the new normal. Reporters made calls to their editors or recorded videos on their phones. One near the scene of the incident told me he heard five shots; another said he heard four. An embassy official said the sound of gunfire had reminded him of his time in Afghanistan.

Jamie Raskin, a Democratic congressman from Maryland, told me he had been thrown to the ground by the Secret Service. “People were screaming and yelling,” he told me. “People were terrified. People seem to be relieved now but it definitely looks like the evening is over.”

Frank Luntz, a consultant and pollster who has long warned of poison seeping into the body politic, said: “It bothers me that it seems like people feel justified screaming, hollering, threatening, throwing rocks, throwing stones, behaving in an awful way and I hope that you in the UK never have to go through this. You went through this during the IRA. Let us hope that it’s not coming here tomorrow.”

For a while it seemed the dinner would resume. I imagined Trump seizing the moment, just as he did while bloodied after the assassination attempt in Butler, Pennsylvania, with a “the show must go on” performance that might have charmed even critics in the room. But protocol dictated otherwise and the dinner was postponed.

The president retreated to the White House and held a briefing for reporters, many wearing their gala finery. He could not resist using the incident to justify one of his pet projects. “I didn’t wanna say this but this is why we have to have all of the attributes of what we’re planning at the White House. We need the ballroom.”

Peter Doocy of Fox News asked why this keeps happening to Trump. The president cited Abraham Lincoln and said: “I’ve studied assassinations, and I must tell you, the most impactful people ... the people that do the most, the people that make the biggest impact, they’re the ones that they go after.”

Which was not the real story. The past 10 years have witnessed a shooting at a congressional baseball practice, a deadly white supremacist march in Charlottesville, the January 6 insurrection at the US Capitol and the killings of the former Minnesota house speaker Melissa Hortman and her husband and the rightwing activist Charlie Kirk. Political violence is rampant and on Saturday, in a fancy Washington ballroom, Trump and the media glimpsed the edge of the abyss.