In today’s fast-moving world, where people are constantly on the move, countries are finding it harder to decide who gets to be a citizen. Take Noura Ghazoui, for example. Born and raised in Italy, she’s fluent in Italian, thinks in Italian, and even dreams in Italian. But when she tried to land a job at her hometown’s town hall, she hit a wall. Why? Because Italy, like much of Europe, ties citizenship to bloodlines, not place of birth.

“I feel Italian,” she says, “but my country doesn’t see me as one.”

For decades, European nations have mostly leaned on ancestry to decide citizenship, while the U.S. has stood out as one of the last countries to grant citizenship to anyone born on its soil, no questions asked. But that’s changing. Recent efforts to curb birthright citizenship in the U.S., temporarily halted by a court order last week, could bring America closer to the European model.

Meanwhile, the surge in migration across both continents is sparking heated debates. Some argue for tighter rules, while others push for more inclusive policies. The question is: How do nations adapt to the realities of a world where borders are blurrier than ever?

As millions of people move across the globe, the rules around citizenship are being put to the test. Will countries double down on bloodline criteria? Or will they rethink what it means to belong in an increasingly mobile world? The answers could reshape millions of lives.