In making nominations to the Supreme Court, Presidents care about diversity, which is a relatively new term for an idea that is nearly as old as the Court itself. In the early days of the republic, when regional disputes were the foremost conflict of the era, nominees were generally defined by their home turfs. So Presidents came to honor an informal tradition of preserving a New England seat, a Virginia seat, a Pennsylvania seat, and a New York seat on the Court. In the nineteenth century, as a torrent of European immigrants transformed American society, religious differences took on a new significance, and Presidents used Supreme Court appointments to recognize the new arrivals’ growing power. In 1836, Andrew Jackson made Roger B. Taney the first occupant of what became known as the Catholic seat on the Court, and that tradition carried forward intermittently for more than a century, with Edward White, Joseph McKenna, Pierce Butler, Frank Murphy, and William J. Brennan, Jr., occupying the chair. In 1916, Woodrow Wilson nominated Louis D. Brandeis, establishing the Jewish seat, which later went, with brief overlapping periods, to Benjamin N. Cardozo, Felix Frankfurter, and Abe Fortas.
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At the Court, as in American life, the rules of diversity have changed. Regional differences faded long ago. The fact that two Arizonans, O’Connor and William H. Rehnquist, served together for almost a quarter century mattered little to anyone. Religious tensions have also cooled. By the time Bill Clinton named Ruth Bader Ginsburg and Stephen G. Breyer to the Court, the fact that both are Jewish (and replaced non-Jewish predecessors) was little more than a curiosity. If Sotomayor is confirmed, there will be six Catholics on the Court, which is also of minor significance. George W. Bush appointed John G. Roberts, Jr., and Samuel A. Alito, Jr., because they are conservative, not because they are Catholic. (The Catholic Brennan was the Court’s greatest liberal.) More than anything, it seems clear that the President saw in Sotomayor a kindred spirit—a high achiever from a humble background who reflects, as best as can be determined, his own brand of progressivism.”