When Labour’s Keir Starmer was elected as prime minister last month, he planned to tackle some of the long-term issues bedeviling Britain. His first priorities included reviving a stagnant economy and repairing the struggling National Health Service. Now, he faces a more immediate and unexpected problem, one that is proving to be his government’s first major domestic test. England and Northern Ireland have been rocked by a week of anti-immigrant riots that have gripped cities and towns and escalated over the weekend. He was born and raised in Britain and, according to the BBC, his parents are from Rwanda.