What are the main security threats facing the UK?
State plots by Russia and Iran are joined by renewed efforts from Islamic State and al-Qaeda, and younger far-right extremists

MI5 has "a hell of a job on its hands", according to its director-general.
Russia and Vladimir Putin's "henchmen" are "on a sustained mission to generate mayhem on British and European streets", said Ken McCallum, in the security service's first yearly threat update since 2022. The UK also faces "plot after plot" by Iran. The two autocratic states are acting with "increasing recklessness", with the number of investigations into state threats shooting up by 48% in the last year.
The most concerning trend is "the worsening threat from al-Qaeda, and in particular from Islamic State", he told a press conference in London. It all adds up to "the most complex and interconnected threat environment we've ever seen".
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What did the commentators say?
In the past, MI5's "menu of significant targets was a limited one", said The Times. Today, "the picture is more varied". Terrorism plots have been joined by a "spectrum of threats from malign state actors like Russia and Iran". And "the sheer number of plots is sobering".
Since March 2017 the UK has disrupted 43 late-stage and potentially deadly terrorist attack plots: "an average of one every two months". Although more than 750 Russian diplomats have been expelled from Europe since the invasion of Ukraine, most of them spies, Russia is still threatening Britain with plots involving "assassination, kidnap and sabotage": effectively a "secret war".
Russia is the "more professional opponent", but the threat from Iran has increased at an unprecedented scale. Since January 2022, intelligence has detected about 20 Iran-backed operations aimed at dissidents and journalists living in the UK.
Elsewhere, IS is "once again firmly in the crosshairs" of MI5, said London news producer Rob Picheta for CNN. Since the fall of its so-called caliphate across Iraq and Syria, the group has "morphed into a terror network" with cells all over the world.
"After a few years of being pinned well back, they've resumed efforts to export terrorism," McCallum said. The deadly concert hall attack in Moscow in March, by IS offshoot Isis-K, was a "brutal demonstration of its capability". Al-Qaeda has also "sought to capitalise on conflict in the Middle East, calling for violent action". Currently, about 75% of counter-terrorism casework is related to Islamic extremism.
But there is another big factor "not to be underestimated", said Sky News home editor Jason Farrell: the far-right. This "dizzying range of beliefs and ideologies", drawn mostly from online conspiracy theories, hatred and disinformation, now accounts for about 25% of MI5's counter-terrorism work. Of all forms of extremism, "lone individuals, indoctrinated online, continue to make up most of the threats".
One in eight people being investigated are under 18 years old – a three-fold increase in three years, and "not something I expected to see", said McCallum. "Extreme right-wing terrorism in particular skews heavily towards young people, driven by propaganda that shows a canny understanding of online culture."
McCallum was "notably less hawkish on China", said Politico. "China is different," he said. "The UK-China economic relationship supports UK growth, which underpins our security."
That raised "a few hack eyebrows", said Politico's London Playbook. Might we describe it as "kindly noises ahead of Rachel Reeves' reported trip to China?"
When asked about the lack of criticism, McCallum said he "had not intended to diminish" the importance of the threat from Beijing.
What next?
"With the levels of threat I've described, the decisions MI5 has to take on allocating our finite capacity are harder than I can recall in my career," the MI5 chief said, with three weeks to go until the chancellor unveils her budget.
When asked whether MI5's caseload was too high, as it was in 2022 when Parliament's Intelligence and Security Committee warned of too much work and not enough funding, McCallum responded: "Things are absolutely stretched."
The UK terrorist threat level remains at "substantial" – the third-highest out of five – which means an attack is "likely". At some point, a plot will succeed, said The Times. Still, that is "no reason to abandon" the UK's support of Ukraine and backing of Israel, which is fuelling the increased threat from Russia and Iran.
But the UK "must also look to its young people and how to protect them from the hatred they ingest from the web". One in eight terrorist suspects being under 18 is "a chilling figure".
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Harriet Marsden is a writer for The Week, mostly covering UK and global news and politics. Before joining the site, she was a freelance journalist for seven years, specialising in social affairs, gender equality and culture. She worked for The Guardian, The Times and The Independent, and regularly contributed articles to The Sunday Times, The Telegraph, The New Statesman, Tortoise Media and Metro, as well as appearing on BBC Radio London, Times Radio and “Woman’s Hour”. She has a master’s in international journalism from City University, London, and was awarded the "journalist-at-large" fellowship by the Local Trust charity in 2021.
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