Chief Justice John Roberts arrived at the Valletta campus of the University of Malta on July 3, 2012, to teach a class on Supreme Court history. As he emerged from the back seat of a black sedan, he held his brown leather briefcase in front of him, almost as a shield. He wore a blue blazer, striped button-down shirt, and tan khakis. His clothes looked crisp, though his face was haggard. He was as exhausted and distressed as he had been in years.

Roberts had left behind a storm in Washington over his opinion upholding President Barack Obama’s health-care overhaul — the Affordable Care Act — a stunning validation of Obama’s signature domestic achievement that transformed public perceptions of the chief justice.

Republicans in Congress had been fighting the law dubbed Obamacare at every turn for two years, and all the GOP presidential candidates in 2012 had vowed to repeal it. And now Roberts, a nominee of President George W. Bush, had saved it.