Societies that are tolerant, free and diverse tend to be richer and happier than societies that aren't. Maryland has shown this for decades.

Now is the time to extend the legacy by legalizing same-sex marriage. The move would beam welcome signals not just to gays and lesbians but to all members of the young "creative class" who represent the economic and social future. Not coincidentally, it's the right thing to do.

More and more research shows how inextricably linked tolerance and prosperity really are. No religion, race or sexual orientation has a monopoly on talent. States wanting to stay ahead must show that their doors are open to everybody.

Statistically, a large gay population is one of the best predictors of a strong economy, economic theorist Richard Florida noted in The Rise of the Creative Class.

"To some extent, homosexuality represents the last frontier of diversity in our society, and thus a place that welcomes the gay community welcomes all kinds of people," he wrote. "Openness to the gay community is a good indicator of the low entry barriers to human capital that are so important to spurring creativity and generating high-tech growth."

Of course you can carry Florida's observations too far. Trying to start a "gay business district," as Spokane, Wash., did after he spoke there a few years ago, won't bring high-tech nirvana without arts, music, diversity and other attributes the creative class craves.

Some attempts to put gay marriage and the Chamber of Commerce on the same bandwagon are just silly.

Last year, the UCLA School of Law's Williams Institute found that increased wedding-hall rentals from same-sex nuptials would help generate a net gain for Maryland's budget of $3.2 million a year. Folks on both sides of the debate can tell you the stakes are lot higher than a couple of coins in the state till.

But as part of a larger policy of openness and benevolence, legalizing gay marriage makes sense for Maryland. We already boast the culture, tolerance, diversity and educational resources the creative class seeks. Allowing unions for two people who love each other - no matter what their gender - will cement the franchise.

And don't be surprised if they bring economic dividends.

Tolerance toward gays is crucial to Baltimore's future as a high-tech hub, a study by the University of Baltimore's Merrick School of Business found a couple of years ago. Metro Baltimore's "Gay Index," as measured by a professor at Carnegie Mellon University, outranked those of Chicago, Philadelphia, Cleveland and St. Louis.

Such a drawing card can help make Baltimore the first Rust Belt city to successfully transform into "an inclusive, diverse and creative economy," wrote Zoltan Acs, the University of Baltimore study's author.

It's not that gays and lesbians are more likely to seek high-tech, high-paying jobs than heterosexuals. Rather, intelligent, creative people of any sexual orientation are more likely to feel comfortable in places that foster tolerance. Companies wanting to hire them must find them on their own turf.

It boils down to attracting youth, who of course are tomorrow's work force. With a median age of 37, Maryland's population is older than that of 30 other states, including Virginia, California, Georgia, Utah and Texas. Young people are more likely to pick up stakes for attractive areas. They're also more likely to support gay rights and gay marriage.

History has demonstrated the wages of inclusiveness and its opposite. Spain's expulsion of Muslims and Jews in the 1400s prompted a long decline. Welcoming Jews, Huguenots, artists and scholars helped make the Dutch Republic powerful and rich in the 1600s despite an almost complete lack of natural resources.

Nobody chooses to be gay. But by approving gay marriage, Maryland can choose to improve its record of equal opportunity for everybody, which is the only way to run an economy.