Good morning, this is Eleanor Ainge Roy bringing you the main stories and must-reads on Tuesday 13 March.

Top stories

Theresa May has said it is “highly likely” Russia is the culprit behind the Salisbury attack on a former Russian spy and his daughter, and the UK will not tolerate a “brazen attempt to murder innocent civilians on our soil”. In a statement to the House of Commons the prime minister said the evidence had shown the Skripals had been targeted by a “military-grade nerve agent of a type developed by Russia”.

TThere were only two plausible explanations for what happened in Salisbury, she said: “Either this was a direct act by the Russian state against our country. Or the Russian government lost control of this potentially catastrophically damaging nerve agent and allowed it to get into the hands of others.”

Labor says it can collect a cool $11.4bn in short-term savings by cutting a cash refund to wealthy investors. Peter Costello introduced the cash payment portion of the dividend imputation, which is a tax offset given to shareholders who get paid dividends from companies that have already paid tax on their earnings. Labor’s plan to scrap it is expected to mainly hit wealthy retirees whose income comes in the form of tax-free superannuation payments.

An Iranian refugee who has been waiting 18 months on Nauru for critical heart surgery has been flown to Taiwan for the life-saving operation after the Australian Border Force relented and allowed the woman’s teenage son to travel with her. Fatemeh, 55, has been facing “high and imminent risk of … heart attack or sudden death”, according to doctors. Border Force had approved her medical transfer overseas, but Fatemeh refused to leave her son alone on the island. He has suffered from acute mental health issues on Nauru. “Death and separation from my son is the same for me,” Fatemeh says.

Labor’s new position on the Adani coalmine has underwhelmed voters, according to the latest Guardian Essential poll. Bill Shorten said last week Labor would oppose the Carmichael project but not revoke its licence if it won office. In this week’s poll, voters were asked whether they supported the Turnbull government’s pro-Adani position, Labor’s stance, or the Greens policy, which is to oppose the project. The highest level of support was recorded for the Greens’ anti-Adani position (30%), followed by the government’s position of supporting Adani (26%) with only 19% backing Shorten.

The former foreign minister Bob Carr has called for Australia to cut its immigration rate in half, declaring that the nation’s experiment of running the fastest rate of immigration in the world was was failing. Monday’s ABC Q&A program concentrated on just one issue: immigration levels and the pressures on our cities. But while Sydney was one of the great melting pots of the world, Carr said, even immigrants were asking whether Australia could achieve the same benefits from migration at a less dramatic pace. “Do we really want to be adding a million to our population every three and a half years?”

Sport

Australia started the fourth day on 180 for five, a lead of just 41 runs, and could only add 59 more runs amid a tail-end collapse, totalling 243 & 239, with South Africa 382 & 102/4. Kagiso Rabada ripped through the remainder of Australia’s order, to leave South Africa’s victory a formality.

The issues with last week’s hiring of Graham Arnold as Socceroos coach go beyond his appointment and to the footballing environment in which he became the leading local candidate. In comparison to other Australian coaches with club experience on a national level, the 54-year-old was not the best person for the job, but arguably the least unsuitable.

Thinking time

For those who have not been glued to the political contest that reaches its denouement in South Australia on Saturday, Max Opray has prepared this handy explainer. He lays out the key players, the big issues and the seats to watch on Saturday night when Nick Xenophon faces his first test as a genuine option for state premier.

What were you like at 21? In a dispatch from the Adelaide festival, Guardian Australia’s culture editor, Steph Harmon, writes about the Swiss artist Mats Staubs’ audiovisual project 21: Memories of Growing Up. The artist travelled the world recording 10 to 20 minutes of audio from people of all ages, races, backgrounds as they described their 21st year. Three months later, the project revisited these people – but this time a camera was turned on them. The audio of each person telling their story was played back to them, and their reaction filmed, as they listened to one past version of themselves describe another. “Watching these strangers grapple with their memories, and how to construct their own narratives, you think of the story you would tell,” Harmon writes. “What kind of person were you? And which words would you use to describe that?”

It’s been 10 years since the global financial crisis and just as many Australians in their prime earning years are employed as in 2008. But the workplace has been radically altered, writes Greg Jericho. “One of the problems with economics is trying to judge how things are going. The unemployment rate used to be a good measure but one clear sign of how poor it can be occurs when you compare our current unemployment rate of 5.5% with the US’s 4.1%. It would seem we’re doing much worse, whereas I’d take our economy any day of the week.”

What’s he done now?

The Trump administration has backed away from a proposal to raise the legal age to buy certain guns because of an NRA lawsuit, the president wrote on Monday. “On 18 to 21 Age Limits, watching court cases and rulings before acting,” Donald Trump tweeted, after weeks of voicing support for raising the age limit. He also said there was “not much political support (to put it mildly)” for the policy. Time magazine has compiled the president’s stance on five gun control ideas here.

Media roundup

The Daily Telegraph reports that the federal children’s minister, David Gillespie, has said adoption rules should be relaxed so white Australians can adopt Indigenous children to rescue them from rape, assault and neglect. The ABC has an interactive experiment giving readers the chance to decide on how Australia’s population should grow. Offering 24 potential pathways for the country, based on projections from the Australian Bureau of Statistics, is Australia full, or is there room for more?

Coming up

The financial services royal commission will begin its first round of formal hearings in Melbourne today, focusing on inappropriate lending in home loans, car loans and credit cards.

The Senate committee inquiry in response to the redress scheme proposed by the child sexual abuse royal commission is due to report today.

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