British Prime Minister Boris Johnson says the <a href="https://www.thenationalnews.com/world/uk-news/2021/09/10/londons-new-911-exhibitions-mark-20th-anniversary/" target="_blank">9/11 terrorists </a>failed to undermine the faith of “free peoples” in a speech to mark the 20th anniversary of the attacks. In his address, at a memorial event at the Olympic Park in east London on Saturday, Mr Johnson said that while the terror threat remained, people have refused to live their lives in “permanent fear”. He said that recent events in Afghanistan have only strengthened people’s belief in freedom and democracy, “which will always prevail over every foe". “Twenty years ago, September 11, 2001, became, in former US president Franklin Delano Roosevelt’s words after Pearl Harbour, a ‘date which will live in infamy',” he said. “On a crystal clear morning, terrorists attacked the United States with the simple goal of killing or maiming as many human beings as possible, and by inflicting such bloodshed in the world’s greatest democracy, they tried to destroy the faith of free peoples everywhere in the open societies which terrorists despise and which we cherish. “And it is precisely because of the openness and tolerance of the United States that people of almost every nationality and religion were among the 2,977 murdered on that day, including 67 Britons, each of them a symbol of the eternal friendship between the United Kingdom and the United States. “But while the terrorists imposed their burden of grief and suffering, and while the threat persists today, we can now say with the perspective of 20 years that they failed to shake our belief in freedom and democracy; they failed to drive our nations apart, or cause us to abandon our values, or to live in permanent fear." Mr Johnson said that Saturday's gathering in east London demonstrates “the failure of terrorism and the strength of the bonds between us". His words come as the head of Britain's <a href="https://www.thenationalnews.com/world/uk-news/2021/09/10/six-terrorist-attacks-foiled-in-uk-during-covid-19-pandemic/" target="_blank">domestic intelligence service</a> said on Friday that the Taliban's takeover of Afghanistan has “emboldened” extremists and could lead to further atrocities. Ken McCallum said MI5 had disrupted six “late-stage” plots developed during coronavirus lockdowns over the past 18 months, and 31 in the past four years. Commemoration events are being held around the world on Saturday for the anniversary of September 11, including several in London. A group called the September 11 UK Families Support Group plans to hold a private remembrance service in Grosvenor Square memorial garden and will hold a candlelit vigil afterwards. On Saturday, London Mayor Sadiq Khan also paid tribute to those who lost their lives. "The terror attacks on September 11 2001 changed our world forever," he said. “Today, we remember the innocent people who lost their lives – including the 67 Britons, many of whom were Londoners. “Our values of freedom, tolerance and respect will always, always prevail. Hate will never win.” The Queen has marked the 20th anniversary of the 9/11 terror attacks with a message to the President of the United States. “As we mark the 20th anniversary of the terrible attacks on September 11 2001, my thoughts and prayers — and those of my family and the entire nation — remain with the victims, survivors and families affected, as well as the first responders and rescue workers called to duty," she said. “My visit to the site of the World Trade Centre in 2010 is held fast in my memory. It reminds me that as we honour those from many nations, faiths and backgrounds who lost their lives, we also pay tribute to the resilience and determination of the communities who joined together to rebuild.” Opposition Labour Party leader Keir Starmer laid flowers at the 9/11 memorial in London. "This anniversary is a chance for all of us to say we too will never forget them," he said. Acting US ambassador, Philip T Reeker, said the special relationship between the United States and the UK remains “so crucial to all of us" and said the US would be “forever grateful” for the “enduring friendship”. A special changing of the guard ceremony during which the US national anthem was played took place at Windsor Castle on Saturday to mark the anniversary. Hundreds of people gathered inside and outside the walls of the castle to watch as the Band of the Welsh Guards processed through the gates then struck up the Star Spangled Banner. The anthem was played at Buckingham Palace 20 years ago on September 12, 2001, in solidarity with the victims of the atrocity. Saturday’s rendition was followed by a minute’s silence. Mr Reeker said the ceremony was a reminder that the US had “no closer ally” than the United Kingdom. “It’s an incredible privilege to represent my country today on this sombre anniversary but at this ceremony,” he said. “We’re incredibly grateful to her Majesty the Queen for the playing of our national anthem. “(It) represents the friendship and solidarity between our two countries, the United States and the United Kingdom, and united is the key word. “This has shown the special relationship remains so crucial to all of us. “Speaking for the United States, we have no closer ally and no closer friend in good times and in bad times, and we are very much reminded of that today … through the enduring relationship between our two countries.”