When President Obama made a landmark speech against modern slavery on Tuesday, many of us in the news media shrugged. It didn’t fit into the political narrative. It wasn’t controversial, so — yawn — it wasn’t really news.

But women like Sina Vann noticed. She’s a friend of mine who was trafficked as a young girl from Vietnam into Cambodian brothels — where she was regularly punished by being locked inside coffins with scorpions and biting ants. Now an anti-trafficking activist with the Somaly Mam Foundation, she sent me an exuberant e-mail (in fractured English, her third language) with a message for Obama: “We are survivors here so proud of you, you are the big president in U.S. and you take action of trafficking. So you give victims from around the world have hope.”

Rachel Lloyd, a survivor of human trafficking who was nearly choked to death by her pimp, felt the same way. Lloyd now runs a superb program in New York City, GEMS, to help American girls escape “the life.” She told me that watching the Obama speech was “one of the most gratifying moments in my 15 years of work on the issue.”

If Representative Todd Akin’s remarks about “legitimate rape” provoked an uproar, shouldn’t it be incomparably more offensive that millions of human beings are still trafficked in the 21st century? Yet the world often scorns the victims and sees them as criminals: these girls are the lepers of the 21st century.

So bravo to the president for giving a major speech on human trafficking and, crucially, for promising greater resources to fight pimps and support those who escape the streets. Until recently, the Obama White House hasn’t shown strong leadership on human trafficking, but this could be a breakthrough. The test will be whether Obama continues to press the issue.

I’ve been passionate about human trafficking ever since I encountered a village in Cambodia 15 years ago where young girls were locked up, terrified, as their virginity was sold to the highest bidder. It felt just like 19th-century slavery, except that these girls would likely be dead of AIDS or something else by their 20s.

Granted, not all prostitution is coerced. Reasonable people can disagree about what to do in the case of adults who sell sex voluntarily. Put aside that disagreement, for we can agree to place priority on the millions of children and adults compelled to provide sex or other labor.

Prostituted kids are among the most voiceless of the voiceless around the world, and it will make a difference if the White House speaks up for them — and fights for them.

On the India/Nepal border, I once chatted with an Indian policeman who was on the lookout for terrorists and smuggled DVDs but was uninterested in the streams of Nepali girls passing through, destined for the brothels in Bombay and Kolkata. The policeman explained that America was pressuring India on movie piracy, so let’s show India and the world that we’re also concerned with enslaved children.

If we tell other countries to free their slaves, we also have to clean up our own act. Contrary to public opinion, the worst of America’s human trafficking arguably doesn’t involve foreign women smuggled into the United States, but homegrown girls.

It’s a disgrace that police officers and prosecutors routinely go after such teenage girls — often runaways fleeing abuse or other impossible situations — and treat them as criminals, while showing less interest in the pimps who exploited them.

Normally, if a man has sex with a young girl, he risks jail and she gets counseling. But, if she has a pimp who earns $50 from the transaction, then everything changes: The man may get a slap on the wrist and the girl may go to jail. Does that make any sense?

So let’s demand that police officers and prosecutors go after pimps and johns, while treating the teenagers as victims who need comprehensive social services.

Republicans have done superb work on this issue in the past, but now they’re balking at straightforward reauthorization of the Trafficking Victims Protection Act — landmark legislation against human trafficking. What are they thinking?

One person on the front lines here in the United States is Alissa, who has a scar on her cheek from where her former pimp mutilated her with a potato peeler as a warning not to escape. She did get away and now works with prostituted girls in Washington whose average age, she says, is 14. Alissa is her street name; she doesn’t want her real name published because pimps still harass her.

Alissa watched Obama’s speech, and then replayed it four more times. She has always been treated as a “throwaway,” she said, and now she was dazzled that the president was treating the issue as a priority.

Some 150 years after the Emancipation Proclamation, let’s make sure that this isn’t just a speech, but a turning point.