On the first day of 2023, Xu was in no mood to celebrate the new year. He had just arrived in the Colombian beach town of Necoclí along with dozens of other Chinese citizens, weary from a two-day bus trip from Ecuador. Their goal was the US via the Darién Gap, a roadless, lawless and extremely dangerous stretch of rainforest connecting South and Central America. He wanted to leave China far behind him. “After I leave the country [China], I have no plans to go back alive,” says Xu later,…