Crossbench Peer | IISS Chair | Strategic Adviser | Former Cabinet Secretary and National Security Adviser |

London
Mark Sedwill retweeted
Could Taiwan be a flash point for future tension between the US and China? Xi Jinping has urged President Trump to take the "correct position" on the self-governing island which Beijing claims as its own. But the US is bound by law to provide Taiwan with the means to defend itself. Mark Sedwill, former National Security Adviser, tells #R4Today that China is likely to continue to exert pressure.
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We’re delighted to welcome the @FinancialTimes as our Media Partner for AFF26. The FT will help shape and amplify the Forum’s content programme, with a special edition of the Political Fix podcast, hosted by @LOS_Fisher, also to be recorded on board HMS Prince of Wales.
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Whether Europe can turn the money it has now promised into forces was the question that hung over Prague last week at the @IISS_org Defence Summit. The money argument is settled. European defence spending has nearly doubled in recent years, and the procurement mix has improved - up from a quarter to 36% of budgets. Several nations now outpace Britain. The real problem is fragmentation. Europe deploys roughly 5x as many military systems as the United States. Without proper integration - in command, industry and doctrine - we get less bang for every taxpayer buck or euro or pound. There's also a political task. The relationship between citizen and state is shifting back toward shared resilience and defence responsibility. Most Europeans haven't caught up, because most politicians haven't made the case. In a democracy, you win that argument only by making it. The IISS Strategic Dossier released for the summit measures the gap between current capability and what's required. It's substantial 👇 iiss.org/publications/strate…
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As we count down to AFF26 in Oslo, Lord @marksedwill reflects on our ties with Norway and the importance of taking AFF to the High-North.
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Mark Sedwill retweeted
A pleasure for me to introduce Gen David Petraeus to deliver the @LordSpeaker's lecture. At this critical time in our history, the future isn't something that simply happens to us; it's shaped by choices, alliances, leadership. David understands that very well. My thoughts:
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Mark Sedwill retweeted
Former @CIA director and 4-star US Army General David Petraeus delivered a compelling @LordSpeaker's lecture @UKHouseofLords on defence & national security. His military leadership & experience at the very highest levels of 🇺🇸 intelligence offer important lessons for us all.
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Mark Sedwill retweeted
🗣️The extraordinary relationship between the @CIA, @NSAGov, MI5, #MI6 and @GCHQ is one of the West's greatest enduring strategic advantages. Former @USArmy General and ex-CIA director David Petraeus speaking @UKHouseofLords
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Mark Sedwill retweeted
Britain’s next leader is right that much of Labour’s agenda can be driven “more agile governance closer to communities”, writes Mark Sedwill, a former cabinet secretary. “But conventional devolution of powers and budgets will not cut it” econ.st/4xX02gp Illustration: Dan Williams
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I've written in @TheEconomist on why Andy Burnham's first 24 hours will define his premiership. No10 North may as well be called Manc-a-Lago unless he's serious about real decentralisation 👇 economist.com/by-invitation/…
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Mark Sedwill retweeted
I see the current defence investment plans "falling well short of what is required", former defence secretary John Healey tells the Commons bbc.in/4vMiAxN
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John Healey’s resignation spotlights the gap between Britain’s defence ambitions and the budget. We can’t do everything everywhere. General Sir Nick Carter and I explain why Dan Jarvis must make hard choices: redesign the force to mobilise via reserves, focus on the northern flank through JEF leadership and protect our global interests. telegraph.co.uk/news/2026/06… #UKDefence #NATO
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Mark Sedwill retweeted
He’s right
This week the most advanced AI model on the planet got switched off by a foreign government. British researchers were studying it. British companies were testing it. British hospitals were piloting it. Not any more. This isn't an AI story. It's the story of every industry we used to lead. Britain has some of the best AI talent in the world. DeepMind was built here. Our AI Safety Institute writes the rules other countries follow. We have the researchers, the universities, the standards. What we don't have is the power stations to run the data centres, the planning system to build them, or the industrial base to make the chips. So the work happens here and the value lands somewhere else. We invent. Others build. Others decide. Then we read about it on Saturday morning. Same story as the kit our soldiers don't have. Same story as the factories we used to. I spent nine months in government making this argument inside the room. I'll make it louder from outside.
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Mark Sedwill retweeted
I think we are all pointing in the same direction . Integrated force not balanced forces. Redundancy in order to confront what is coming up (quantum , a resort to exotics like bio and chemical and genetic) it would be good to get round a table and discuss everything , such as carrier strike,CASD, reserve forces . Get it across something CAN be done as well as needs to be done.
The ‘Balanced Force’ was taken apart here, in 2022 (👇). Healey bought into the idea of a joint MSHQ to direct the creation of an ‘Integrated Force’. It made Labour’s manifesto. Landslide=mandate. Yet the institutional inertia of ‘UK Defence’ resists it. policyexchange.org.uk/wp-con…
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Thanks Robert. Jarvis has two weeks until the NATO summit but could set new direction at DefMin meeting this week. Let’s hope he grasps it.
Really on point on the Today programme : integrated force not balanced force - will they do it ? Need to articulate a set of priorities and then carry them out - fast !
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Britain can't sustain a “balanced force” We need integrated forces to protect the North Atlantic and High North against Russian aggression and hold their Arctic bases at risk. Those forces can also deploy to wherever the next Hormuz crisis erupts. It's the only credible strategy in a world where American security guarantees are no longer unconditional.
New DefSec Dan Jarvis might have to live with the budget total Healey and Carns couldn’t accept. But he must rewrite the Defence Investment Plan to transform defence and make the tough choices we need. / 1
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New DefSec Dan Jarvis might have to live with the budget total Healey and Carns couldn’t accept. But he must rewrite the Defence Investment Plan to transform defence and make the tough choices we need. / 1
NATO as a protected enterprise is finished. US won’t keep the sea lanes open alone. Britain’s answer is expeditionary forces — anchoring NATO’s northern flank and reaching the Gulf and Indo-Pacific. My latest @spectator: spectator.co.uk/article/mini…
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Mark Sedwill retweeted
My letter to the Prime Minister
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Mark Sedwill retweeted
Congratulations to Prime Minister @narendramodi on becoming India’s longest-serving elected Prime Minister. A remarkable milestone in the world’s largest democracy and good for the UK-India partnership which will continue to go from strength to strength.
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Mark Sedwill retweeted
Within hours of being announced as the nominee to be the U.S. Director of the CIA, I received a hand-delivered message on MI6 stationery congratulating me on my nomination. It was signed simply "C" in green ink. Legendary. I shared it with my son and even he thought I was now cool! More than that, this note, from Sir Alex Younger, Chief of the Secret Intelligence Service of the United Kingdom, confirmed what I already believed: the work that the CIA and MI6 did together mattered, that the partnership was critical, and that two leaders focused on the mission could save lives and provide tools for our nations to deter our adversaries. Alex's passing this week brought back so many memories of our time in service together. He flew to Langley to see me the day I was confirmed. We brought our two senior teams together in the UK to plan and coordinate and build in the first several weeks of my time on duty: making clear to them all that this relationship was more than special - it was critical for the security of our two countries. Alex was a remarkable intelligence partner. When we needed help, it wasn't "let me see;" it was "this matters to you and America we'll get it done." And he and his team always did. I think he knew we would do the same for him and his team and his nation. Many Americans are alive today because of his leadership of MI6, I never knew how to thank him enough. Alex became a friend as well. In the years since we both left office we would see each other from time to time. He was always so kind, so thoughtful, so smart. His deep love of his country was surpassed only by his deep commitment and love of his family. Decent and proper - and funny as hell - Alex was "C." As espionage requires, he was quiet, not attention seeking. He knew what evil was and he was ruthless in his efforts to crush it with every legal tool at his command. And he knew who his friends were and committed himself to supporting them. I miss Sir Alex Younger. He was a role model for me and a man with whom every minute I spent was valued and savored. Blessings to you Alex. Praying for you and for your family. Well done and may you rest in peace in His hands.
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Day 2 of Brother Phil’s charity walk in memory of our late mother. Please support with whatever you can. instagram.com/reel/DZPJxGCMC…
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