Until Thursday morning, it had been nearly four centuries since the arrest of a senior British royal. On his 66th birthday, the late Queen Elizabeth’s favourite son was detained on suspicion of misconduct in public office. By evening, the former prince was released from police custody. But the ongoing investigation will unpick years of lurid allegations about Andrew’s ties to the disgraced US financier Jeffrey Epstein that have heaped embarrassment on his brother, King Charles. The arrest of...