If you take the rickety E train down to the World Trade Center stop and then follow the directions for the -in early September- still sweltering corridor towards the PATH station, you’ll arrive, just past the station officer’s booth, at a metal glass door marked with distinctive bright orange sprayed numerals. Those sliding doors are among the few artefacts still operational from the subterranean superstructure that existed underneath the World Trade Center complex a quarter of a century ago. The markings were made by rescuers two days after the atrocity which New York City will remember this weekend. The X denoted an unsafe area, the date of 9/13 confirms that it was searched two days after the towers came down.

On Tuesday, as the city bore into what will be a heavy week of remembrance, it was difficult to avoid the ongoing politicisation and political ramifications of the horrors of that day set against the rolling stories of extraordinary valour, and kindness, and heartbreak which sprang from it. In the morning, mayor Zohran Mamdani held a conference, flanked by family members of those lost to mark the release of some 170,000 previously withheld city records on the air quality in and around lower Manhattan in the days after 9/11.

An estimated 9,000 people, many of them among the secondary responders who worked for nine months through the unfathomable wreckage, have died from 9/11-related illnesses since. That figure will only grow in the years ahead, even as the day itself recedes into history.

“Now, close to twenty-five years later more people have died from 9/11-related illnesses than were killed on the day itself,” the mayor said.

“It would be one thing if government stood alongside survivors and provided them with everything they needed every step of the way. And yet we know that could not be further from what actually happened. People got sick because the leaders they trusted lied and told them they were safe to breathe in toxic air. And then, when they began to contend with the symptoms of the illnesses that followed the government that had not hesitated to send them into harm’s way was nowhere to be found.” Among the heavily-castigated city decisions that have come into focus was the advice given to downtown residents of homes close enough to have fallen under the extraordinary dust-cloud which rumbled through the lower part of Manhattan island that morning.

“The city began covering their ass three weeks in, in a memo; the memo is entitled ‘legislative alternatives to the fiscal responsibility for 9/11,” the comedian and television show host Jon Stewart, who has been part of the campaign group, said at the conference.

“These people had to fight sick and dying for years. There was poison on the ground and in the windowsills and in your air conditioners and covering your pets and your clothes. And it stayed there for months. Everyone knew. And now it’s very clear that the city knew as well. And rather than take the steps that would ameliorate the damage that would cause to its citizens, and to the people that were down there, they instead covered it up to get back to business as usual. But unfortunately, business will never be usual again. So, I just want to say that people standing up here are heroes.”

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The release of the information was at once a victory for the campaigners and another example of the ways in which the after-effects of the al-Qaeda attacks continue to intrude on thousands of New York families.

“We knew that the air was not safe to breathe. We have to remember that the federal government and epa all said it was … even though there was that horrible acrid smell in the air for days and weeks, we were told to stay downtown,” Julie Menin, the speaker of the New York City council, who lost her mother to a 9/11-related illness, said on CNN on Tuesday. She grew up in a home close to the World Trade Center.

“What the federal government did in those first few days was they told us to stay downtown. They told us time and time again that the air was safe to breathe even though it’s not rocket science to know clearly it was not: you could smell it in the air. In the first early days when the towers fell you could barely see a couple of inches in front of you and the toxins that were in there- asbestos and pcbs and environmental toxins were obviously incredibly detrimental.”

Almost a quarter of a century later, the complexity of how to remember 9/11, and honour those who were murdered, requires a kaleidoscopic lens by New Yorkers. It’s a deeply sombre and painful week for the city- and still unbearable for those who lost loved ones and who directly survived the attacks. It is also a heavily symbolic week of remembrance- a true inflection point- for the United States in general. The broadcast networks have run the famous documentaries about the day itself and a poignant feature on the history of the ‘Windows on the World’ restaurant, which was, briefly, the most sought-after restaurant table in the city. All week, individual fire houses are holding ceremonies. Social media has been filled with the brief tributes to the extraordinary lives of the unknown people who went to work in the towers that day, and of the first responders who rushed to their aid. The photographs of many young faces, dated and frozen in the fashion and hairstyles of the day, have acquired a terrible articulacy all on their own.

Against that, the hopeless partisan divide which has come to define American political discourse has begun to dominate the official element of Friday’s remembrance ceremony. Rudy Giuliani, feted as a hero as New York City’s mayor in the days and weeks after 9/11, has publicly called on Mamdani not to attend Friday morning’s official ceremony at the World Trade Center. “Having lost friends there and being very close to many of the families, it offends me that he is coming.”

In a separate request, John McDevitt, president of the Port Authority Retired Police Association, called for Mamdani and two other Democrat politicians not to attend, as the day should be ‘a solemn day of remembrance’ and not a ‘political occasion, a photo opportunity or a platform for public officials.’ An online petition started by Giovanni Galante, made a widower that morning, asking the mayor not to attend had gathered some 101,000 names by this week.

Mamdani, the first Muslim to hold the office of mayor, has become a figurehead for Republican politicians eager to spotlight the socialist dimension of the Democratic Party, often with blatantly Islamophobic messaging. He has been criticised for marking previous 9/11 remembrances with social media messages focusing on the deaths caused by the Bush administration war on terror in Iraq and Afghanistan more than on those killed in the World Trade Center attacks.

This week will represent a solemn inquisition of his political skills and instincts. A new Suffolk poll found that 56 per cent of New Yorkers believe Mamdani is doing a ‘good or excellent’ job in his first year while a further 17 per cent find his performance fair. 74 per cent believe he should be at the World Trade Center ceremony.

For his part, Mamdani has been steadfast in his commitment to honouring those who lost their lives at Friday’s ceremony. All four living retired presidents- Joe Biden, Barack Obama, Bill Clinton and George W Bush – will be at the ceremony; president Donald Trump will be represented by his vice president, JD Vance.

“I think that the focus of memorial services should be on the New Yorkers who were killed that day, their families, the survivors, the first responders. I don’t think it should be on politicians,” Mamdani said on Tuesday, declining to comment when asked whether he believed then mayor Giuliani had ‘lied’ to the city about the air safety in the weeks afterwards.

“I leave it to New Yorkers to make their judgments. What we want to do is finally allow them the documents that they have long been demanding.”

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