This is America in Pursuit, a limited run series from ThruLine and NPR.

I'm Rundab de Fet-Dagh.

Each week, we bring you stories about life, liberty, and the pursuit of happiness in the U.S. that began 250 years ago.

As we've been talking about in this series, who is American and what it means to be American have always been in flux.

And today, that's still true.

Just this month, the Supreme Court started hearing oral arguments that those born in the United States are automatically U.S. citizens, regardless of

their parents' immigration status. The court will issue a decision this summer and either

undo birthright citizenship or uphold the precedent set over a century ago by another Supreme Court

case, the case that started at all.

The question to be determined is whether a person born within the United States, whose father and mother were both persons of Chinese descent and subjects of the Emperor of China,

but at the time of the birth where both domiciled residents of the United States is a citizen.

Today, Ramtin and I bring you the story of Wang Kimark, the man behind the Supreme Court case that made birthright citizenship the law of the land.

Until now.

That story, right after a quick break. Music of the land, until now.

That story, right after a quick break. It all began when Wong Kim Ark, a San Francisco-born cook,

tried to return to California after visiting China, his parents' homeland.

I think when he saw San Francisco Bay emerge out of what was likely the foggy morning.

This is Amanda Frost, Professor of Immigration Law and author of You Are Not American, Citizenship Stripping from Dred Scott to the Dreamers.

He must have been thrilled to think, I'm finally back home and I can get off this boat and go back to my home in San Francisco.

But that's not what would happen.

To Wang Kim-Arts surprise, a U.S. customs agent declared that he was not allowed to get off the ship and set foot onto U.S. soil.

At this point, the Chinese Exclusion Act was in effect.

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