f the Conservatives thought they knew a way to ruin Keir Starmer’s prospects of becoming prime minister, the onslaught would have begun already. Under Boris Johnson’s management, Downing Street is a campaigning machine with a sideline in government. The absence of attack on the opposition leader is unlikely to express non-partisan reticence. The better explanation is a lack of ammunition. In parliament Johnson has only tried a few disparaging remarks about Starmer’s background as a lawyer presumably because No 10’s obsessive opinion-mining operation has found a seam of wavering voters who despise the legal profession. Out of public view, Dominic Cummings reportedly dismisses the Labour leader as a “remain lawyer”, the worst kind. That would be a resonant jibe if Starmer were intent on re-litigating the old dispute over EU membership, but he has taken the opposite approach. To the dismay of grieving remainers, the Labour leader is not even urging the government to extend Brexit transitional arrangements. He has judged that Johnson’s willingness to hear sense on Europe shrinks to zero as soon as the opposition demands it. The prime minister is eager to re-enact referendum battles and Starmer has a healthy disinclination to fight battles he cannot win. The Labour leader is not volunteering to be the soft target his enemies want him to be. That, more than any policy shift, represents a strategic rupture from the Jeremy Corbyn era, although stalwart supporters of the former leader do not see it in those terms. They feel betrayed because Starmer won the leadership with praise for the radical left and now looks ready to bury it. Affronted Corbynites cannot hold Starmer to the small print in his mandate because there is none. He won with a campaign of vague left platitude. He said there was too much policy in the 2019 manifesto, but not which bits should have been excised. He later sacked Rebecca Long-Bailey, but for amplification of antisemitism on Twitter, not for excessive attachment to nationalised industry. Corbyn himself complains not about the new regime but alleged sabotage of the 2017 election campaign that almost ousted Theresa May, but didn’t. His dutiful followers squeeze the bellows of social media outrage on to the cold ashes of their first, glorious defeat because they have no one but themselves to blame for the second, ignominious one last December. The best illustration of Starmer’s method for navigating tricky positions is his response to the toppling of Edward Colston’s statue in Bristol: the monument should have been taken down long ago, he said, but mob action was the wrong method. To radical protesters that sounded like cavilling on a subject that permits no moral equivocation – Britain’s slave-trading past. But Starmer was trying to combine that ethical clarity with recognition that a candidate to be prime minister cannot go on the record endorsing criminal damage, nobly motivated or otherwise. He could smell the follow-up attack line. What other acts of vandalism do you endorse, Mr Starmer? Such is the tightrope that opposition leaders walk. The alternative is launching yourself into the air, followed by a rush that feels like flight but ends in a crash. Some Conservative MPs, being traditionally more promiscuous with their beliefs than their Labour counterparts, are impressed by Starmer’s style. Privately they concede that his seriousness and respectability are sorely lacking in the Tory leader. He also has an easy affinity for the policies of state intervention and welfarism made necessary by the coronavirus. That feature of Labour’s leftward swerve under Corbyn will be preserved. The longer the pandemic goes on, the more pressure there is on Tories to help its victims and the further they will stagger from their free-market, fiscal disciplinarian comfort zone. The more potential there is then for the opposition to demand munificent government without being caricatured as Bolsheviks. The vital component is a leader who looks like a responsible custodian of other people’s money. When Tory chancellors tax, borrow and spend, voters know it is strictly business, while suspecting Labour of doing it for pleasure. The diligent lawyer style that Johnson seems to think is so unattractive in Starmer might help deal with that vulnerability. In the language of crude focus-group tests, the swing voter might rather have a pint with the prime minister, but if they had lent one of the two leaders a tenner there can’t be much doubt as to who they would sooner trust to pay it back. A general election is a long way off. There is every possibility that Starmer’s rival will be a different Tory leader by the time it comes. Johnson is a wasting asset and his party is not sentimental when it feels an upgrade is necessary. Starmer will be forced into many more contortions to woo new voters that will alienate some part of his current support base. How to win in Brexitland and Remainia? How to recover swathes of Scotland lost to nationalism? The polling and parliamentary arithmetic are daunting. It will take some innovative electoral gymnastics to reach all the constituencies Labour needs for a winning coalition. It is easy to list the obstacles and traps in Starmer’s path, but at least he seems to know where they are and how not to blunder into them. It is a ponderous method that does not provoke roars of approval from his own side. And yet it elicits a more subtle and valuable form of flattery – silence from the Tory attack machine. • Rafael Behr is a Guardian columnist