Some are referring to girls and women who are enslaved, transported from country to country, and forced to work in brothels. Others mean girls who are essentially kidnapped, shuttled from motel to motel, sold for sex and subject to violence from pimps and johns.
But federal law defines sex trafficking broadly to include all children involved in prostitution with a pimp. Some even interpret the law as covering all minors involved in prostitution at all. This includes girls who seek out a pimp for work, who are engaged in prostitution in their hometowns, whose families know about their prostitution, and even those who turn down opportunities to leave their "traffickers." In some ways, sex-trafficking laws are similar to statutory rape laws – the government has determined that a minor simply cannot consent to being involved in this sort of commercial sex.
The law upon which much of the US anti-trafficking work is based, and to which many advocates trace the start of the domestic anti-trafficking movement, is the Trafficking Victims Protection Act 2000. The UN adopted its own anti-trafficking protocol the same year.
At first, the US law focused primarily on problems abroad. This made sense, according to those who worked on the legislation. The international numbers for human-trafficking victims were – and are – high: The UN has estimated human trafficking to be a $32 billion global industry; in 2008 it estimated that 2.5 million people from 127 countries were trafficked – 79 percent for sex, the rest for other forms of labor, from farm work to sweatshops. Many are children.