Jeremy Corbyn has taken the hugely controversial step of blaming Britain’s foreign wars for terror attacks such as the Manchester suicide bombing.
The Labour leader claimed a link between “wars our government has supported or fought in other countries and terrorism here at home”, as he relaunched his party’s election campaign on Friday after the three-day pause.
Mr Corbyn stressed that his assessment is shared by the intelligence and security services and “in no way reduces the guilt of those who attack our children”.
“Those terrorists will forever be reviled and held to account for their actions,” he said.
But, vowing to “change what we do abroad”, he added: “An informed understanding of the causes of terrorism is an essential part of an effective response that will protect the security of our people, that fights rather than fuels terrorism.
“We must be brave enough to admit the ‘war on terror’ is simply not working. We need a smarter way to reduce the threat from countries that nurture terrorists and generate terrorism.”
In the speech, the Labour leader also linked the Manchester atrocity to Theresa May’s failure to ensure “the police have the resources they need”.
“Austerity has to stop at the A&E ward and at the police station door. We cannot be protected and cared for on the cheap,” he said.
“There will be more police on the streets under a Labour government. And, if the security services need more resources to keep track of those who wish to murder and maim, then they should get them.”
He continued: “No government can prevent every terrorist attack. If an individual is determined enough and callous enough sometimes they will get through.”
But it is Mr Corbyn’s determination to link the 22 deaths in Manchester with Britain’s involvement in the war on terror that is certain to trigger a backlash.
In the speech, he did not name any specific wars, having – as a backbencher – opposed the conflicts in Afghanistan, Iraq, Libya and against Isis, in Iraq and Syria.
At the Iraq Inquiry in 2010, Baroness Manningham-Buller, the former head of MI5, said the invasion had “substantially” increased the terrorist threat to the UK, by radicalising young people.
Mr Corbyn was one of just 13 MPs to oppose David Cameron and vote against the Libya bombing in March 2011.
After the overthrow of Muammar Gaddafi, Libya descended into bloody chaos, with two rival governments and the growing menace of jihadi extremism.
Libyans in the UK, including in Manchester, have spoken of their fear that the growing Islamist radicalisation in their home country was also taking root among refugees who moved here.
And intelligence briefings have suggested Salman Abedi, the Manchester suicide bomber, moved to Libya, before returning to Britain as recently as last week.
But, strikingly, Mr Corbyn delivered his speech just days after the tragedy and while the police and intelligence services continue to conduct an investigation it is expected to take many months.
His pledge to change foreign policy suggests he would end involvement in air strikes against Isis in Iraq and Syria, where 1,250 British military personnel are stationed.
The contrast with Ms May could not be starker, after she backed Nato becoming a formal member of the coalition fighting in the region.
Mr Corbyn’s speech comes after Ukip claimed the Prime Minister shared the blame for the Manchester attack because she failed to prevent Abedi from returning to Britain.
“It is also a dereliction of duty to allow jihadis to return to this country, including it seems, Monday night’s terrorist,” said Ukip leader Paul Nuttall.
Suzanne Evans, Ukip’s deputy chair, added that Ms May “must bear some responsibility” for the deadly attack, because she forced through police cuts and failed to cut immigration.
Speaking in central London, Mr Corbyn called for “the solidarity, humanity and compassion that we have seen on the streets of Manchester this week to be the values that guide our government”.
Britain must ensure “we never surrender the freedoms we have won and that terrorists are so determined to take away”, he added.
The election campaign will get back up to full speed on Friday, after the cross-party agreement to put activities on hold as a mark of respect.
Even without Mr Corbyn’s speech, attention was likely to focus on the stance of the party leaders on security issues, police funding and the terrorist threat.
It may mean less scrutiny of plans for the NHS and social care, just four days after Ms May’s embarrassing U-turn over a cap on care costs and the collapse of her manifesto proposals.
Join our commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies