Massachusetts is not exporting gay marriage.

If gay marriage isn't legal in their home state, a gay couple can't get married in Massachusetts, says the Massachusetts Supreme Judicial Court:

In an opinion written by Justice Francis X. Spina, the court upheld a 1913 statute that says that no out-of-state resident can get married in Massachusetts if the marriage would be void in the person's home state, unless the person intends to live in Massachusetts....

The original lawsuit was filed by eight out-of-state couples and 12 cities and towns, claiming the 1913 statute was discriminatory and had been invalidated by the legalization of gay marriage in the state....

[Governor Mitt] Romney said in an interview: "This is an important victory for traditional marriage and for the right to each state to be sovereign as it defines marriage. It would have been wrong for this court to impose it's same sex ruling on the other 49 states of America."

Only one justice, Roderick L. Ireland, dissented, writing that "the commonwealth's resurrection of a moribund statute to deny nonresident same-sex couples access to marriage is not only troubling," but "also is fundamentally unfair."