It’s 20 years since a clear, sunny morning in downtown Manhattan was transformed at 8:46am.

Four planes were hijacked on the east coast of the USA: two hit the World Trade Center. One hit the Pentagon, the heart of the country’s defence. Another went down in western Pennsylvania. It was a day that left nearly 3,000 dead.

It was a day that changed everything: from the way we live and travel and the threats we fear, to the global world order and modern terrorism. All of which still lives on today, from New York City to Kabul.

In today’s episode, Jon Snow takes us back to that fateful, generation-defining day, and recounts his visit to Ground Zero in November 2001. And a warning: this content contains distressing themes.

Downing Street has said the government will introduce vaccine passports for nightclubs and other crowded indoor venues in England and Scotland from the end of September, subject to votes in both parliaments.

For some, this makes sense: a public health measure that allows us to return to normality safely, and perhaps acts as an incentive to get vaccinated.

For others, it’s a threat to our way of life, and as we have seen in some countries where they’ve already been introduced, people are angry.

We look at the pros and cons of Covid passports, and turn to Israel, a country that has been using a type of domestic Covid passport since February.

Sources: Reuters, DW News, News For All, YouTube: Clive Harris 

For more than a year, Australia and New Zealand were sanctuaries away from the pandemic world.

But the Delta variant snuck in through Australia’s strict quarantine borders and called the whole strategy of Covid elimination into question.

With lockdowns affecting half of the population in Australia - and some tired of the endless cycles - the country has now shifted focus: Australia says suppressing Covid to zero is impossible and vaccinations will allow them to live with the virus.

But that shift has not been repeated in New Zealand. Jacinda Ardern has stuck to her original plan, believing strict and quick lockdowns combined with increased vaccinations can completely suppress the Delta wave.

What's next for both nations as they go their different ways?

Sources: Sky News, DW News, 7:30, 7 News

First it was Nando's, then McDonald's, and finally Greggs. Supply issues at major chains have forced a shortage of milkshakes and chicken, with the problems this summer seen as a warning of what's to come.

We speak to Business and Global Trade Correspondent Paul McNamara to discuss why there aren't enough lorry drivers and workers - and why the British workforce isn't queuing up to take the vacancies.

How bad could this all get? Could it damage our economy? And is this just the tip of the iceberg as we head for the winter months - with another Covid wave possible?

In China, women have had enough. There's a feminist awakening as groups challenge laws and customs, which they believe are entrenched in sexist ideas.

But as the movement grows, the ruling Communist Party wants to shut it down, labelling these liberal attitudes as contrary to their growing nationalist agenda. 

Today, we speak to the reporter, Jessie Lau, who tells us about the women on the front line of China's feminist fight back and we ask whether the MeToo movement in China can prevail. 

Sources: YouTube: TanWeiWei, DW News, CNN, ITV News

Italy was the first European country to feel the full force of Covid-19. The images of army trucks carrying bodies and of deserted streets in Milan and Rome were the first inkling we had, in Europe at least, of what was to come.

Antonello Guerrera, a journalist for the Italian newspaper la Repubblica, talks about how those scenes are embedded in the minds of Italians, forming a solidarity and caution that could mean they are more likely than others to embrace vaccinations and vaccine passports.

And do the recent sporting triumphs represent a redemption for the country, after the despair of 2020?

Sources: Sky Sports, Andrea Bocelli, CGTN, NBC News, France 24

Our climate is changing, and the consequences are playing out right before our eyes.

As the UN issues a "code red for humanity", Anja Popp is on the front line of our warming planet, reporting on floods in Germany and fires in Greece. In today’s episode of The Fourcast, she tells us what it’s like to witness the devastating consequences of climate change up close.

And our climate journalist Simon Roach explains what the recent IPCC report means and what, if anything, can be done about our rapidly warming planet.

If you thought the summer of sport was over, think again. It’s not just the football that’s back, it’s the Paralympics tomorrow.

But just like with the Olympics, with Covid cases increasing in Tokyo, there will be no spectators to watch the athletes.

Today, our sports reporter Jordan Jarrett-Bryan, who is out in Japan, tells us what we can expect from Team GB, who have finished in the top three in every Paralympics since the turn of the century. 

We ask how much has the Paralympics changed minds in society about people with disability - and do we finally put these games on a similar level to the Olympics?

Sources: CNN, World Watch News

Afghanistan is once again under the control of the Taliban, 20 years after the US Army and its allies forced them into retreat. When Joe Biden announced the withdrawal of US troops, there were immediately concerns that this could all happen. And yet no one foresaw the shocking ease at which Taliban forces swept through the country, taking city after city, and eventually the capital Kabul.

We’ve been here before: when the Russians left in 1989, the Soviet-backed regime lasted just a few years. This time, the American-backed administration lasted mere weeks. Why was it so easy for the Taliban to regain control? And is this really a new-look Taliban - or is the future still just as bleak for the women and girls of Afghanistan?

In today’s episode, we once again chat with our international editor Lindsey Hilsum about where this leaves the West’s status as defenders of freedom and liberty, and we ask, what was the point of the last 20 years of bloodshed?

Last month, UNESCO stripped Liverpool of its World Heritage status, saying that developments along its waterfront were damaging the historic value of its docks.

The last decade has seen the Liverpool skyline transformed - with new buildings popping up alongside the famous Three Graces.

Yet the latest batch of modern high-rises and a new football stadium have pushed UNESCO to their limit - and yet the council are pushing on regardless.

This is about heritage versus regeneration, about trying to re-energise a city as well as ensuring the past is preserved. 

How do you do that and please all sides?

In this episode, we spend time in Liverpool speaking to those on both sides of the debate to figure out how a city can become the perfect mix of the modern with the historic.