The U.S. government has moved quietly and aggressively to prevent undocumented Indians from entering the United States, many of whom are Sikhs fleeing political repression or economic collapse at home. ... The number of Indian nationals caught trying to cross the southern border into the U.S. exploded suddenly in 2010, growing sixfold to 1,200 from just over 200 the year prior. ... Although the number has oscillated since then, it has remained near an all-time high. And that includes only those caught trying to cross undetected, leaving out Buta Singh and others like him — thousands, mostly young men, who walk up to a border crossing, turn themselves in, and plead asylum. The total number of Indian nationals who tried to enter the U.S. without papers, including through airports and other points of entry, also spiked in the last five years, peaking at close to 13,000 in 2013, more than double the number in 2009. ... Much of this influx, according to dozens of interviews with immigrants, experts, and current and former immigration officials, comes from young Indian men at the border, ferried there by transnational smuggling networks. Although border authorities do not track the religious or regional origins of migrants, government officials and other observers say that large numbers of the new arrivals are Sikhs from Punjab, a region in northwestern India beset by economic collapse and environmental degradation, a major drug epidemic, and decades of what human rights groups describe as political violence carried out with impunity.