But the modern era has been something of a disaster for unanimity. Chief Justice Earl Warren was able to achieve unanimity only 36.1 percent of the time; Chief Justice Warren E. Burger, a scant 35.8 percent. One of Chief Justice William H. Rehnquist’s final public acts was to express exasperation at the fractured court. In 2005, on the final day of his final term, a frail Rehnquist described his last majority opinion by first outlining his views, then the three concurrences filed, and then the three dissents filed, and joking, “I didn’t know we had that many people on our court.” Compare that talk, and those numbers, to what Chief Justice John G. Roberts Jr. achieved this year with his colleagues.

People remember Chief Justice Roberts’s 2005 confirmation hearing for his statement that his job would be to call balls and strikes. But something else he said is worth remembering: that he would try to bring about “a greater degree of coherence and consensus in the opinions of the court.” He pointed to Warren’s leadership in Brown as an example.

Unanimity, of course, would mean little if it were reserved only for minor things. But the court was unanimous this term in cases that posed big central questions, like whether the government could search your cellphone without a warrant, whether software could be patented, whether the rules for class-action securities lawsuits should change, and many others. Those cases were not easy ones. In the cellphone case, the government made forceful points about the ways in which those searches were permissible, and indeed necessary, for law enforcement. The software industry and its foes argued vociferously about whether software patents were destroying the economy or creating it. And so on. What’s more, the court wasn’t unanimous because the justices sat on their hands; to the contrary, they reversed the lower court 74 percent of the time this year.

Many justices have pointed out the importance of published dissent. There is no doubt that dissents can serve a useful role by explaining when a justice thinks the majority has gone off the deep end. But unanimity also sends its own powerful message — one that might be eclipsed in the headlines by a sensational dissent, but could ultimately have a greater impact. Take the abortion decision on Thursday, which was unanimous in its bottom line, but not in its reasoning. Chief Justice Roberts joined four justices appointed by Democratic presidents — the same lineup that saved the Affordable Care Act two years ago, that time for a liberal result, unlike Thursday’s.

This path, of trying to forge places of agreement even among people who are inclined to disagree, is the essence of what the American experiment is all about. In an era when the leadership of the House of Representatives is suing the president, when people across the aisle cannot even be in the same room with one another, the modesty and cultivated collegiality of the nine members of the Supreme Court this year remind us all that there is another way.