Roberts, C. J., dissenting
a man and a woman.” Ante, at 6. Early Americans drew heavily on legal scholars like William Blackstone, who regarded marriage between “husband and wife” as one of the “great relations in private life,” and philosophers like John Locke, who described marriage as “a voluntary compact between man and woman” centered on “its chief end, procreation” and the “nourishment and support” of children. 1 W. Blackstone, Commentaries *410; J. Locke, Second Treatise of Civil Government §§78–79, p. 39 (J. Gough ed. 1947). To those who drafted and ratified the Constitution, this conception of marriage and family “was a given: its structure, its stability, roles, and values accepted by all.” Forte, The Framers’ Idea of Marriage and Family, in The Meaning of Marriage 100, 102 (R. George & J. Elshtain eds. 2006).
The Constitution itself says nothing about marriage, and the Framers thereby entrusted the States with “[t]he whole subject of the domestic relations of husband and wife.” Windsor, 570 U. S., at ___ (slip op., at 17) (quoting In re Burrus, 136 U. S. 586, 593–594 (1890)). There is no dispute that every State at the founding—and every State throughout our history until a dozen years ago—defined marriage in the traditional, biologically rooted way. The four States in these cases are typical. Their laws, before and after statehood, have treated marriage as the union of a man and a woman. See DeBoer v. Snyder, 772 F. 3d 388, 396–399 (CA6 2014). Even when state laws did not specify this definition expressly, no one doubted what they meant. See Jones v. Hallahan, 501 S. W. 2d 588, 589 (Ky. App. 1973). The meaning of “marriage” went without saying.
Of course, many did say it. In his first American dictionary, Noah Webster defined marriage as “the legal union of a man and woman for life,” which served the purposes of “preventing the promiscuous intercourse of the sexes,… promoting domestic felicity, and… securing the
