What landmark decision legalized same-sex marriage in the U.S.?

The landmark decision that legalized same-sex marriage in the United States is Obergefell v. Hodges, issued by the Supreme Court in 2015. This ruling was significant because it declared that same-sex couples have a constitutional right to marry under the Fourteenth Amendment, which guarantees equal protection and due process. The case emerged from several lawsuits challenging state bans on same-sex marriage, and the Court's decision affirmed that denying marriage rights to same-sex couples violated the principles of equality and liberty.

This ruling represented a critical advancement in the LGBTQ+ civil rights movement, as it officially recognized the right of same-sex couples to legally marry nationwide, effectively overturning previous state-level prohibitions and ensuring that marriage rights were consistent across the country. The decision built upon a broader historical context of civil rights struggles in the U.S., reflecting changing societal attitudes towards LGBTQ+ individuals and relationships.