Naomi Osaka is the toast of Japan after winning the Australian Open last weekend and becoming the first Japanese player to be ranked No. 1 in the world. She faces an awkward deadline, however. Japan’s Nationality Law requires Japanese who have additional citizenships to choose just one when they turn 22. Osaka, who holds both U.S. and Japanese passports, reaches that age later this year. Though Japan has rarely enforced the rule, Osaka’s celebrity poses a challenge to a country historically obsessed with national and ethnic identity. She most likely won’t be able to dodge the decision.

Her dilemma is hardly unique in Asia. While many other parts of the world have been opening up to the benefits of dual-nationality, Asia’s wealthiest and most populous economies — including Singapore and China — have stubbornly resisted doing the same. It may be time to rethink that opposition. Countries that welcome dual citizens are magnets for globalized talent and capital — two things Asia’s aging societies are increasingly going to need if they want to remain vibrant and growing.

Historically, citizenship was viewed as a kind of exclusive relationship, permanently committing the individual to the nation. In cases of international marriage and children, citizenship was typically assigned on the basis of the husband’s and father’s citizenship. This could have ugly consequences: As recently as the 20th century, American women who married Chinese, Filipino or Japanese nationals automatically forfeited their U.S. citizenship in favor of their husband’s. As of 1960, more than half of the world’s countries stripped nationality from anyone who voluntarily adopted the citizenship of another nation.

This conception of citizenship began to erode after World War II. As cross-border marriages became more common, many countries (including the United States) chose to accept multiple citizenships without legal consequence. Today, three-quarters of the world’s nations allow their citizens to acquire a second citizenship without automatic repercussions.

In some cases, particularly countries with large diaspora populations, the process is even encouraged. In December, for example, Lesotho amended its constitution to allow for dual citizenship, hoping to reverse decades of brain drain and lure home native-born nationals who lost citizenship when they acquired, say, U.K. passports.

Similarly, in 2016, Mexico — which for decades opposed dual citizenship — began actively encouraging Mexicans who legally reside in the U.S. to acquire American citizenship. The goals are several, including a desire to see Mexican-Americans more active in U.S. civic life, ensure that their legal interests are protected in the U.S. (especially in the current anti-immigrant climate) and facilitate U.S. investment in Mexico.

These are more than just hopes. Academic studies suggest that countries that recognize dual nationalities enjoy greater rates of return migration and overseas remittances than those that don’t. Equally important, at least one recent study demonstrated that citizens who are forced to choose often renounce their original nationality, particularly if, as in the case of China, citizenship rights might be viewed as insufficient compared with other countries. Meanwhile, another recent study suggests that selective programs (recognizing dual citizens from certain countries only) can be an effective means of attracting targeted talents and demographics.

It’s no surprise then that several Asian governments have changed long-standing policies on dual citizenship in hopes of accruing these benefits, including South Korea, Vietnam and the Philippines. Elsewhere in the region, however, progress is stalled for a range of reasons, including security concerns (India and China), fragile senses of national identity (Singapore and Malaysia) and concerns about ethnic purity (Japan).

While understandable, such resistance is short-sighted. Several of these countries, including India and China, have been afflicted by damaging brain drains; allowing dual citizenship might attract at least some expatriates to come home to work. For more developed economies such as Japan and Singapore, dual citizenship can serve as an added incentive as companies compete for an increasingly globalized talent pool. It might also provide a small but not insignificant bulwark against aging and shrinking populations.

The Justice Ministry estimates there are roughly 890,000 Japanese dual nationals, including individuals assumed to have multiple nationalities based on birth to non-Japanese parents. Osaka, the country’s current darling, is one of them. Rather than force her to choose her identity or — worse — remain in the legal shadows, it’s time for Japan and other Asian countries to recognize her and her compatriots as representatives of the region’s globalized future.

Adam Minter is a Bloomberg Opinion columnist. He is the author of “Junkyard Planet: Travels in the Billion-Dollar Trash Trade.”