When a newspaper columnist takes time off to, say, write a book, the paper will note: ?So-and-so is on hiatus, but his column will return.? It?s sometimes unclear whether this is a promise or a threat.

The same thing can now be said about the Defense of Marriage Amendment. The Senate, by refusing to consider a constitutional amendment to protect traditional marriage, has put the issue on hiatus. But it will return.

To see why, let?s track the likely course of marriage over the next few years. For now, the 1996 Federal Defense of Marriage Act remains law of the land. It defines marriage as the union of one man and one woman, and says no state will have to recognize a ?marriage? performed in another state that doesn?t meet this definition.

But at the same time, our traditional policy of federalism remains in place, which means each individual state may define what ?marriage? is. The Massachusetts Supreme Judicial Court ruled last year that marriage is ?the voluntary union of two persons as spouses, to the exclusion of all others.? According to the justices, ?the right to marry means little if it does not include the right to marry the person of one?s choice.?

So for now, two men can be legally married in Massachusetts, but, if they move next door to New Hampshire, that state can refuse to recognize the marriage.

That?s clearly untenable. Indeed, legal challenges are already underway. A lawsuit in Florida argues DOMA violates both the equal protection and full faith and credit guarantees of the U.S. Constitution.

According to Heritage Foundation scholar Matthew Spalding, that challenge stands a good chance of success. ?Assuming the Supreme Court follows the logical trend of its own precedents and jurisprudence of recent decades, it would be inconsistent for a majority of the Justices not to redefine marriage,? Spalding writes. That means nationwide recognition of same-sex marriage. Here?s where things start to get expensive.

Consider again the words of the Massachusetts court: Marriage is the ?voluntary union of two persons as spouses, to the exclusion of all others.? That bestows the rights -- and benefits -- of marriage on any two people who want them for any reason.

Imagine two men living together. They?re not homosexual, but they are good friends who?ve roomed together for years. One of these men loses his job. This is a big problem, because he?s got some serious health problems. The other man, however, has excellent health benefits.