With its discreet design, flavored pods, and an advertising strategy that seemed to deliberately target kids, Juul quickly came to dominate the vaping industry. Altria, the tobacco giant behind Marlboro, bought a nearly $13 billion stake in the company, valuing it at $38 billion. But just as fast, Juul found itself in the crosshairs of public health experts, regulators, and ultimately Congress for its role in fueling a nationwide youth nicotine epidemic.