Tuesday’s top story: Sanders denies Warren camp’s claim that he said no woman could beat Trump in 2020. Plus, the Oscar bait that couldn’t catch a nomination

Good morning, I’m Tim Walker with today’s essential stories.

Friction between progressive candidates as first 2020 votes loom

The progressive senators Bernie Sanders and Elizabeth Warren have long considered each other friends. The two even met in Washington in late 2018 to discuss maintaining good relations as they prepared to launch their 2020 presidential campaigns. But as the first primary votes approach, tensions between the two camps have spilled into the open, with Warren claiming a resurgent Sanders told her at that meeting that he did not believe a woman could beat Donald Trump – a claim Sanders described as “ludicrous”.

Cory Booker. The New Jersey senator on Monday became the latest high-profile candidate to drop out of the 2020 presidential race, citing a lack of funds – and leaving the little-fancied late entrant Deval Patrick as the only African American in the field.

Russian hackers. A US cybersecurity firm has claimed Russian military hackers tried to steal internal emails from Burisma, the Ukrainian energy firm that employed Hunter Biden which was at the centre of attempts by Trump last July to pressure Ukrainian authorities to announce an investigation into the Bidens for purported corruption, an effort that has led to the president being impeached.

Pompeo claims Suleimani killing is part of bigger strategy

Facebook Twitter Pinterest Pompeo speaks in California on Monday. Photograph: Philip Pacheco/AFP via Getty Images

The Trump administration has again altered its justification for the killing of Qassem Suleimani, with the US secretary of state saying the Iranian general’s assassination was part of a broader strategy to deter US foes, including China and Russia. Speaking at Stanford University on Monday, Mike Pompeo made no mention of the White House’s original assertion that Suleimani had been plotting imminent attacks on US assets. Pompeo has declined to attend a House foreign affairs committee hearing on the killing, set for Tuesday.

Canadian victims. The Canadian prime minister, Justin Trudeau, has said the 176 victims of the jetliner accidentally downed by Iran last week – 57 of them Canadian – would still be alive if not for the recent escalation of tensions partly triggered by the US.

Iran arrests. Tehran says arrests have been made over the shooting down of the Ukrainian airliner, which has led to days of protests and driven at least two hosts for the state broadcaster to quit. The crisis presents an opportunity for the US, writes Julian Borger, but it is unclear whether Trump will grasp it.

US’s deadly ‘heat islands’ linked to racist housing policy

Facebook Twitter Pinterest In Denver, Colorado, researchers found a 12-13F temperature difference between formerly ‘redlined’ and non-redlined neighbourhoods. Photograph: PR

Extreme heat kills more people in the US each year than any other hazardous weather event. Now a landmark study has found urban heatwaves disproportionately affect low-income neighbourhoods, due in large part to the legacy of a long-banned racist housing policy. Temperatures in different parts of the same city can vary by up to 20F, researchers found – and the hottest neighbourhoods, or “heat islands”, are those which have historically had fewer green spaces and tree canopy, and more concrete and pavements.

‘Redlining’ legacy. The new study examined the link between those heat islands and the historic, racially motivated town-planning policy known as “redlining” – which was banned in 1968, but whose demographic effects linger on.

Queen gives reluctant blessing to Harry and Meghan’s plans

Facebook Twitter Pinterest The Duke and Duchess of Sussex plan to walk away from some of their royal duties and spend more time in North America. Photograph: Alastair Grant/AP

The Queen has reluctantly agreed to the Duke and Duchess of Sussex’s plans to downgrade their royal status and split their time between the UK and Canada, following a crisis summit of senior royals at Sandringham on Monday. In a statement, the Queen stressed that although she would have preferred them to remain full-time royals, Harry and Meghan would remain “a valued part of my family” as they undergo a “period of transition” to the more “progressive” roles they have requested.

Canada’s role. Trudeau has acknowledged there will be “many discussions to come” on how Canada will deal with the couple’s security, and whether taxpayers would have to foot the bill.

Rethinking monarchy. Harry and Meghan should be allowed to escape the royal circus, says Suzanne Moore. It will give the rest of us a reason to rethink what monarchy means.

Cheat sheet

A Wisconsin judge has ruled that state election officials must purge 200,000 people from the voter rolls, to the dismay of voting rights activists, who said the ruling is designed to make it harder for students and minority populations to vote.

More than 300 human rights activists were killed in 2019 while working to protect the environment, free speech, LGBTQ rights and indigenous lands, a report has found. The killings took place across 31 countries, but two-thirds of them occurred in Latin America alone.

Scientists in the US have used stem cells from African clawed frogs to create the world’s first living robots . The tiny creatures are “living, programmable organisms” and “entirely new lifeforms,” said one of their creators.

The model Gigi Hadid has told a judge in Manhattan she can “keep an open mind on the facts” as she was vetted to be a potential juror at Harvey Weinstein’s rape trial – despite having met Weinstein and knowing some of his accusers.

Thank you for supporting our journalism in 2020!

More than 30,000 readers from all 50 states have contributed to the Guardian’s fundraiser, helping us raise more than $1.3m. And it’s not too late to contribute, although it will be soon – the fundraiser closes on Wednesday. You can contribute here.

Must-reads

Facebook Twitter Pinterest Clockwise from top left: Cats, The Aeronauts, Just Mercy and Dark Waters. Composite: Working Title Films/Amazon/Warner Bros/Focus Features

The awards season movies that aren’t winning awards

The Academy unveiled its 2020 Oscar nominees on Monday, with Joker leading a field notable for its continued dearth of diversity. But what of those Oscarbait movies that didn’t make the grade? Benjamin Lee looks at the awards-ready films left out in the cold.

How a fitness app became a religion

The Strava app offers community, training data and motivation to millions of athletes, from park-runners to world champions. For an amateur, it’s like having an elite coach in your phone, for free – and it’s totally addictive, as Rose George discovered.

Why are mothers leaving the tech industry?

Half of women working in tech say they have experienced gender bias or discrimination. And the industry’s long hours and bro culture can affect new mothers in particular, making them feel alienated at a time when they need support most, as Georgina Fuller reports.

Life with dementia in Japan

The numbers of people living with dementia in Japan are rising, and the stigma around the condition is at last beginning to fade. Justin McCurry and photographer Robin Hammond document the care facilities devising new solutions for an ageing society.

Opinion

Like Kamala Harris before him, Cory Booker has exited the Democratic presidential race after struggling to gain traction – specifically, says Derecka Purnell, with young voters of colour.

Booker, and his diverse political peers including Julián Castro – who was the only Latinx candidate – Deval Patrick and Senator Harris, are caught between moving further left to capture young people of color, or further right to prove their potential as future establishment candidates.

Sport

LSU quarterback Joe Burrow has capped one of the greatest seasons in college football history by throwing five touchdown passes and running for a sixth score as he led his team to a 42-25 national championship victory against Clemson on Monday night.

The Houston Astros have been fined $5m and deprived of their first- and second-round draft picks in 2020 and 2021 after an MLB investigation found the team cheated by stealing signs from opponents during their first ever World Series winning season in 2017. Manager AJ Hinch and general manager Jeff Luhnow have been fired by the team after receiving one-year suspensions.

Sign up

The US morning briefing is delivered to thousands of inboxes every weekday. If you’re not already signed up, subscribe now.