Civil unions have to be explained and do not get the same respect as a marriage.
Only the word married conveys the universally understood meaning applicable to the lifetime commitment many couples make. Regardless of whether civil union and marriage offer the same benefits and obligations on paper, when the government relegates same-sex couples to civil union rather than marriage, it forces them to explain the difference at work, at school, in hospitals and elsewhere. Those couples lose the respect and dignity that they deserve.
Civil unions create more harm outside the state.
Although the federal government and some states still disrespect same-sex married couples, problems are further compounded for a couple with a civil union. When a couple's own state creates a separate status other than marriage, it makes them even more vulnerable within their state and when they travel to another state.
A separate and unequal status invites others to discriminate.
When the government decides one group cannot have the same option as others, it marks them as inferior and invites others to discriminate against them, as well. Same-sex couples may face discrimination from employers, businesses, police, emergency room workers and others.
Civil unions break the promise of equality.
Civil unions were created as a political compromise, because some people were not ready to provide same-sex couples with the right to marry. The highest courts in four states—California, Connecticut, Iowa and Massachusetts—have said that maintaining a separate legal status like civil unions for a minority, rather than treating everyone the same, is a violation of the constitutional promises of equality.