Keir Starmer has suspended seven of his MPs who rebelled against the whip to scrap the two-child benefit cap. So why won’t Labour scrap the controversial limit, and what does this first test of Starmer’s leadership tell us about the party’s financial position? The Guardian’s John Harris is joined by columnist Gaby Hinsliff and former Downing Street chief of staff and Conservative peer Gavin Barwell to discuss the issue. Plus, the Conservative leadership race begins