As in Europe, civil unions are proving more and more frequently to undermine the institution and traditional role of marriage, as Slate author John Culhane (who supports SSM) argues after interviewing straight couples who opted for civil unions instead of marriage in Illinois:
...When asked during a long Skype interview why she and her partner, Justin Gates, chose to enter a civil union rather than marry, Leah Whitesel, who identifies as queer despite her current relationship, framed the question this way: “Gay marriage doesn’t seem like the right discussion to me. Because it should be: ‘What is this institution of marriage and does it still need to be defined the way it has been?’ ” For Whitesel and Gates, the answer is no.
Many of the other straight civil union pioneers have also said no to marriage—for themselves and as an institution. The evidence is in a report that the Cook County Clerk’s Office recently issued on the nation’s first opposite-sex couples who civilly united. It found dissatisfaction with the institution of marriage because of concerns with its historical assignment of roles, its connection to religion, and its unfairness to gay and lesbian couples. My own interviews with some of these same couples, who have rejected marriage and plunged into the shallower, murkier pool of the civil union, reflect a cohort prepared to take the wrecking ball to marriage itself.