Reformers often argue about how conducive our system is to social change. Some claim that U.S.-style federalism promotes reform by enabling local majorities to enact their preferences. Others assert that a more centralized structure, with the federal government deciding more issues for the entire country, would produce change more quickly. Recent developments with respect to same-sex marriage, in both America and Australia, shed new light on this long-running debate. At first, these developments seem to favor the American model, but the actual story is more complicated (and interesting).

Until a few months ago, America and Australia both had federal laws defining marriage as a union between one man and one woman. In June, the Supreme Court struck downAmerica's Defense of Marriage Act on the ground that it "demeans" and "humiliates" same-sex couples. Both before and after the Court's decision, states rushed to recognize same-sex marriage. According to the latest count, eighteen states, mostly in the East and Midwest, now allow same-sex couples to wed.

In Australia, on the other hand, the High Court did not just decline to nullify the federal definition of marriage in a case decided last month. Instead, the Court relied on the federal definition to thwart an effort by the Australian Capital Territory (ACT), home to Canberra, to authorize same-sex marriage. According to the Court, the ACT law was "not capable of operating concurrently with the [federal] Marriage Act to any extent," and thus was void. The twenty-seven marriages performed under the ACT law were annulled, and today no same-sex couple in Australia can get married.

Read more at The Huffington Post