Excerpt from A Good Provider Is One Who Leaves by Jason DeParle, plus links to reviews, author biography & more

Johnson was spectacularly wrong. In the decades that followed, the foreign-born share of the population soared near-record highs, and immigration set the United States course to become a majority-minority nation. The United States has more than forty-four million immigrants, nearly five times as many as in 1965, and as many as the next four countries combined. The United States has more immigrants than Canada has Canadians. Nearly 90 percent come from the developing world, with eleven million Mexicans trailed, respectively, by Indians, Chinese, Filipinos, Salvadorans, Vietnamese, Cubans, Dominicans, Koreans, and Guatemalans. Non-Hispanic whites, 83 percent of America when Johnson signed the bill, account for 62 percent today. Much attention gets paid to the share of immigrants, about a quarter, who are here illegally and less to the fact that most come through authorized channels. With one in four children in the United States an immigrant or the child of one, it's no exaggeration to say their future is America's.

In a thousand ways, large and small, Johnson wouldn't recognize the society his pen stroke helped create. Immigrants brought a hundred languages to the Des Moines public schools, turned the South Side of Milwaukee from Polish to Latino, and raised mosques in the Washington suburbs. In twenty-five years, the foreign born population of Greater Atlanta rose nearly 1,200 percent. Immigration changed the way Americans eat and the way they pray. It powered the rise of Silicon Valley and redrew the electoral map. It bred cosmopolitanism. It bred resentment. It widened class divides between the affluent, who are most likely to benefit from migration, and the less privileged, who are more likely to bear its costs. It made America more vibrant but less united, wealthier but less equal, more creative but more volatile. Shockingly, the demographic upheaval brought Barack Obama. More shockingly, it brought Donald Trump.

The United States is not alone. About 258 million migrants are scattered across the globe, and they support a population back home as big if not bigger. Were these half billion or so people to form their own country, it would rank as the world's third largest. Just since the turn of the century, their numbers have grown 50 percent. While the movements of the nineteenth century were largely transatlantic, what stands out about migration today is its ubiquity. Ireland elected its first African-born mayor. Mongolians do scut work in Prague. The roster of recent Miss Israels includes one Ethiopian-born. "I went to bed in one country and woke up in a different one," wrote the Irish novelist Roddy Doyle, who peoples his stories of multiethnic Dublin with characters like Fat Gandhi, the Celtic Tandoori King. A few decades ago, migration seemed so irrelevant to international affairs that doctoral students in political science couldn't find professors to guide dissertations. Now it threatens to tear apart the European Union.

My own light bulb moment came in learning that remittances— the sums migrants send home— are three times the world's foreign aid budgets combined. Migration is the world's largest antipoverty program, a homegrown version of foreign aid. Mexico earns more from remittances than from oil. Sri Lanka earns more from remittances than from tea. About $477 billion a year now flows home to the developing world, an increase of more than sixfold in the twenty-first century.

Yet competing with the literature of gain is a parallel literature of loss. About half the world's migrants are women, many of whom care for children abroad while leaving their own children home. "Your loved ones across that ocean ..." Nadine Sarreal, a Filipina poet warns,

Will sit at breakfast and try not to gaze
Where you would sit at the table
Meals now divided by five
Instead of six, don't feed an emptiness

Earlier waves of globalization, the movement of money and goods, were shaped by mediating protocols. The International Monetary Fund regulates finance. The World Trade Organization regularizes trade. The movement of people, the most intimate globalization, has the fewest rules. There is no World Migration Organization to say who has the right to migrate or what rights migrant should have.

Excerpted from A Good Provider Is One Who Leaves by Jason DeParle. Copyright © 2019 by Jason DeParle. Excerpted by permission of Viking. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.