Mosul is today the scene of the largest battle on Earth. Some 100,000 soldiers, police and militiamen are bearing down on the ancient Iraqi city. Backed by Western air power, their mission is to drive out the so-called Islamic State fighters who’ve occupied the city since 2014. Mosul holds enormous symbolic value to both sides. The IS leader declared himself “caliph” there; the Iraqis want to avenge their defeat there nearly three years ago. Between them are hundreds of thousands of civilians. The UN says they face "extreme risks": water, food and fuel are already scarce. This edition of The Inquiry tells the story of the campaign and asks how the final phase could end.

(Photo: An Iraqi Special Forces soldier climbs through a hole in a wall as he searches for Islamic State fighters in Mosul, Iraq, 2017. Credit to: REUTERS/Goran Tomasevic)

Back in 2015 our radios and TV bulletins were full of stories of people trying to get to Europe. We saw distressing pictures as boats sank and lives were lost. Huge numbers of men, women and children tried to make their way by road, rail and foot to Hungary, Germany and beyond. There was anguish and fear in EU capitals. Now the story has slipped from the front pages. We find out what happened next.

(Photo: Syrian refugees sit aboard a dinghy heading to the island of Lesbos early on June 18, 2015. Credit: Getty Images)

Our phones are powerful tools with lots of benefits – keeping in touch, accessing information and services and managing our lives. We are using them more and more, constantly picking them up. Even in situations where it is considered inappropriate, disadvantageous, or even dangerous, many people still find it hard to resist the urge to check their smartphones. Why do we find these mini computers in our pockets so compelling?

Our expert witnesses explain how tech developers are tapping into established behavioural psychology theories about what gets us hooked. We hear how experiments conducted on pigeons can help explain why we cannot resist checking to see whether we have got email or a new like on social media and we reveal the tricks that companies use to keep us coming back for more.

(Photo: People using their smartphones on the platform of a train station in Bangkok. A recent study showed smartphone owners are often connected all day. Credit: Getty Images)

President Trump has made no secret of his contempt for news organizations, stating that the media are "among the world's most dishonest people". He has described The New York Times as "failing", The Wall Street Journal as “a pile of garbage” and CNN as a “terrible organization” responsible for “fake news". The BBC? “There’s another beauty.” The President has made statements and assertions which are false. He uses Twitter to speak directly to the American people. His combative press secretary Sean Spicer said he plans to “hold the press accountable”. All this seems like bad news for what many Trump supporters call – derisively – the “mainstream media”. But might the opposite be true? Might Donald Trump, in fact, be good for journalism? That’s the question on The Inquiry this week.

(Photo: Republican presidential candidate Donald Trump talks to reporters after the first prime-time presidential debate, Quicken Loans Arena, Cleveland, Ohio. Credit: Getty Images)

Since 2006 the WikiLeaks website has been publishing secret documents and material obtained from whistleblowers and other sources. Many of the confidential files published by WikiLeaks have been revelatory. The site has frequently made news around the world. But in 2016 Wikileaks published hacked emails relating to Hillary Clinton and her presidential bid. Those leaks appeared to serve the interests of the Trump campaign and were – according to US intelligence – probably provided to Wikileaks by Russian sources. So, this week on The Inquiry, we’re asking: can you believe what you read on WikiLeaks?

(Photo: Wikileaks founder Julian Assange speaks to the press after appearing at Belmarsh Magistrates court in London, England. Credit: Getty Images)

"No deal is better than a bad deal." So said Britain's Prime Minister Theresa May, clarifying her country's position on Brexit negotiations with the EU. In the absence of a deal with the EU Britain would “revert to WTO rules” after Brexit. But what does that mean, exactly? The Inquiry has the answer. Presenter: Linda Yueh Contributors: Emily Lydgate, University of Sussex Alan Winters, UK Trade Policy Observatory Hosuk Lee-Makiyama, European Centre for International Political Economy Adam Marshall, British Chambers of Commerce

(Photo: German Chancellor Angela Merkel and Britain's Prime Minister Theresa May arrive for a statement prior to a meeting at the Chancellery in Berlin, Germany, on November 18, 2016. Credit: Getty Images)

'Do we want his finger anywhere near the button?' Hillary Clinton asked during the US election campaign, referring to Mr Trump and the nuclear arsenal. But how close is an American president's finger to 'the button'? How close is anyone’s? We explain how the nuclear weapons systems of the US, Russia, Britain and China work – and how much power any one individual has over them.

(Photo: A Trident Ii, Or D-5 Missile, Is Launched From An Ohio-Class Submarine. Credit: Getty Images)

In 2002 US military personnel at Guantanamo Bay in Cuba were given 96 hours to prepare their sleepy base for the arrival of hundreds of prisoners. “The worst of the worst,” they were told. Beyond US jurisdiction, with no clear legal framework, prisoners accused of terror offences have been held there indefinitely without charge ever since. For many, Guantanamo has stained the image of the United States. When President Obama came to power in 2008 he vowed to close it. He failed. In this week’s Inquiry we are telling the full story of Guantanamo - from its creation to the so-called “forever prisoners” held there today.

Presenter: James Fletcher

(Photo: A US soldier walks next to a razor wire-topped fence at the abandoned 'Camp X-Ray' detention facility at the US Naval Station in Guantanamo Bay, Cuba. Credit: Getty Images)

It’s a question humans have asked forever. Are we alone in space? But it wasn’t until the late 1960s that humans started an organised, systematic hunt for extra-terrestrial intelligent life. We have listened to radio waves, peered through the celestial dust and beamed The Beatles to distant planets. So how’s it going? Is there anybody out there? This is the story of the search for extra-terrestrial life.

Presenter: Helena Merriman

(Photo: The ALMA, an international partnership project between Europe, North America and East Asia, with the cooperation of Chile. Credit to Getty)

Food production accounts for as much global greenhouse gas emissions as all forms of transport combined. That’s why many scientists think we can’t tackle climate change without addressing what we eat. So – in this week’s Inquiry – we’re looking at alternative climate-friendly diets and asking what it would take to move the world towards them.

Presenter: Helena Merriman

(Photo: Friends having a vegetarian meal. Credit: Shutterstock)

A lot has gone wrong this year. We are not talking about Brexit or the election of Donald Trump – both of which split opinion in Britain and the US. We are talking about terror attacks, the brutal conflict in Syria, and the thousands of migrants who died trying to reach Europe.

Good things did happen. But the good news was mostly buried under the bad. So we wanted to find about four things that went right in 2016. And, we talked to the people who made those things happen. Four amazing stories united by one thing - the ambition of a small number of extraordinary people to achieve the seemingly impossible. (Photo: Betrand Piccard in his pilot seat, permission from Solar Impulse, Teresita Gaviria watches the announcement made by the Colombian government and the FARC guerrillas, Getty Images, Sophien Kamoun and Dr Herath with kind permission)

It’s a surprisingly simple idea: to end long-term homelessness, give every person living on the streets a home. It can also be surprisingly effective. Medicine Hat, a city in Canada, recently became the first city to end homelessness in this way. The approach is known as Housing First, and – unlike many other homelessness initiatives – it doesn’t require homeless people to make steps towards solving other issues like alcoholism, mental health problems or drug addiction before they get a home. But is this approach solving the problem, or simply moving it off the streets?

Presenter: Helena Merriman

(Image: A homeless man with his dog outside a building. Credit to Getty)