Hard as it always is to say when the rust set in, I think the deciding moment was the immediate aftermath of Boris Johnson’s resignation on July 7. Faced with the rubble of what amounted to an ethical crash — the long disaster of partygate and the allegations of sexual misconduct levelled at former deputy chief whip Chris Pincher — the Conservative leadership contenders agreed silently on a wretched collective strategy: which was more or less to ignore the huge problem of trust, standards in public life and the spectre of sleaze...