You may believe Julian Assange is a narcissist and even a bad person. But what played out in London is dangerous for all of us

It is ironic Assange is being charged by the Trump administration, which he may have helped put in power

It is as shocking now as it was when it was first made public.

Footage taken by two US AH-64 Apache helicopters shows them attacking buildings in Baghdad, and then closing in a group of people. The people are not shooting, they are not even armed, though the US airmen claim they are. Two of them are journalists. Several are children.

When the Americans are given permission to attack, they respond with excitement. “Light ‘em all up.”

The video shows the ghostly silhouette of someone running. “Oh, yeah, look at those dead bastards,” says one airman. Somebody points out there is child who appears to have been injured. “Well it’s their fault for bringing their kids into a battle.”

The recording, filmed in July 2007 as the insurgency against the US and UK invasion of Iraq gathered pace, was many people’s first introduction to Wikileaks. The footage was obtained by army intelligence analyst Chelsea Manning, who – sickened at what was happening in the name of her country – leaked it to Wikileaks and its founder Julian Assange.

At least a dozen people, including Reuters’ staff Namir Noor-Eldeen and Saeed Chmagh, were killed in an incident the Pentagon claimed was justified.

“If those killings were lawful under the rules of engagement, then the rules of engagement are wrong, deeply wrong,” Assange said when Wikileaks released the video in 2010.

Manning served seven years for leaking the video, much of that time spent in miserable solitary confinement. On Thursday, Assange was arrested at the Embassy of Ecuador in London, where he spent seven years having claimed political asylum.

He was detained by the UK government at the request of the US, who has charged him with conspiring with Manning. If extradited and convicted, he faces up to five years in prison.

Nobody need be an admirer of the 47-year-old Assange to be deeply disturbed by what played out on the streets of Knightsbridge, or disgusted by the role of the British government. If a person can be arrested for exposing what were very likely war crimes, what does it say about us as a society that we have allowed it to happen?

As Ewen MacAskill, defence and security correspondent of the Guardian, which has had a love-hate relationship with Assange, tweeted: “Terrible precedent if journalist/publisher ends up in US jail for Iraq war logs and state department cables.”

If Assange had only published what became known as the Collateral Murder footage, he would have been one of our era’s most important whistleblowers. But he also provided more – cables from the US state department, and files relating to the Guantanamo Bay detention camp.

Much of the material was published by newspapers around the world, which makes it harder to understand the glee with which many reporters appeared to react to news of Assange’s arrest. In truth, mockery over his situation has been a constant theme of coverage of the Australian.

It is deeply wrong that a proper investigation was not carried out into allegations of sexual assault levelled at Assange by two Swedish women.

He declined to travel to Sweden amid fears he could be detained on behalf of the US, something that now appears less fanciful than it did at the time. Swedish investigators could have travelled to London. On Thursday, authorities in Stockholm revealed they had been asked to reopen the case. That is a very good thing.

Supporters of Assange told me last year they feared the US was determined to get him after Wikileaks’ 2017 release of Vault 7, which consists of thousands of files on CIA spying. A series of US officials subsequently said they viewed Wikileaks as a threat, among them Mike Pompeo who termed Wikileaks a “hostile non-state intelligence service”. Jeff Sessions said arresting Assange was a “priority”.

It seems the US was provided with this opportunity after Lenin Moreno was elected president of Ecuador in May 2017. He was less disposed to Assange than his predecessor, Rafael Correa.

The US played on this, seeking to develop closer military and diplomatic ties with the South American nation, a country which had long been wary of Washington.

The March 2018 decision to cut off Assange’s internet connection came a day after a high-level US military visit to Ecuador. Last summer, Mike Pence became the first US vice president to visit Ecuador since 1987. He and Moreno specifically discussed Assange.

Assange may be a narcissist. He may have put people in danger by refusing to redact sensitive information. He may have helped Trump get elected, and he must be made to answer the allegations of sexual assault against him.

Yet those things must not cloud our view of what took place today, however difficult it is to place them aside.

A clear attack on the freedom of the press, on the freedom of whistleblowers to publish damaging information about powerful institutions, was carried out on the streets of London. And we all stood by and did nothing.