Ron Johnson’s priorities were clear. “We have a huge problem with skyrocketing crime,” insisted the US senator for Wisconsin, accusing his debate opponent, Mandela Barnes, of pushing to reduce cash bail, release violent criminals and slash police funding. Minutes later it was Barnes’s turn to go on the offensive. Johnson, the lieutenant governor said, had described the end of the constitutional right to abortion as a “victory” and shown himself to be “callous” and “out of touch”. Barnes promised to codify that right into law if elected. A casual observer could have been forgiven for thinking the two candidates were...