It is a sad day in America when the President of the United States endorses sex-selection abortion by opposing the Prenatal Nondiscrimination Act. It is no less sad that this bill did not pass the House — although a significant majority, 246 members, did vote for it — given its laudable aim of outlawing this egregious assault on baby girls.

Sex-selection abortion is cruel, it’s discriminatory and it’s legal. It is violence against women. Most people in government are unaware that it is part of a deliberate plan of population control. This is the real war on women.

Last year, an undercover sting operation by Live Action exposed several Planned Parenthood affiliates who were eager, ready and willing to facilitate secret abortions for underage sex-trafficking victims — some as young or younger than 14. As the prime sponsor of the Trafficking Victims Protection Act, I found the willingness of Planned Parenthood personnel to exploit young girls and partner with sex traffickers to be absolutely appalling.

Now Live Action has released new sting-operation videos — part of a new series, “Gendercide in America” — that show Planned Parenthood personnel advising undercover female investigators how to procure a sex-selection abortion. Caught on tape, one staffer tells an investigator to wait until her baby is 5 months along to get an ultrasound that reveals the sex of the child. Then, if it’s a girl, kill it.

Last week, a Planned Parenthood spokeswoman said in a statement to the Huffington Post: “No Planned Parenthood clinic will deny a woman an abortion based on her reasons for wanting one, except in states that explicitly prohibit sex-selection abortions.”

In other words, Planned Parenthood is okay with exterminating a child in its huge network of clinics simply because she’s a girl. What a dangerous place for little girls. Let’s not forget that Planned Parenthood aborts approximately 330,000 children every year.

For most of us, “it’s a girl” is cause for enormous joy, happiness and celebration. But in many countries, this phrase can be a death sentence. We can’t let that happen here.

In her book “Unnatural Selection: Choosing Boys Over Girls, and the Consequences of a World Full of Men,” Mara Hvistendahl traces the sordid history of sex-selection abortion as a means of population control.

“By August 1969, when the National Institute of Child Health and Human Development and the Population Council convened another workshop on population control, sex selection had become a pet scheme,” Hvistendahl writes. “If a reliable sex-determination technology could be made available to a mass market,” there was “rough consensus” that sex-selection abortion “would be an effective, uncontroversial and ethical way of reducing the global population.”

Fewer women, fewer mothers, fewer future children.

These cruel, anti-woman policies have had horrific consequences.

Hvistendahl writes that today “there are over 160 million females ‘missing’ from Asia’s population. That’s more than the entire female population of the United States. And gender imbalance — which is mainly the result of sex-selective abortion — is no longer strictly an Asian problem. In Azerbaijan and Armenia, in Eastern Europe, and even among some groups in the United States, couples are making sure at least one of their children is a son. So many parents now select for boys that they have skewed the sex ratio at birth of the entire world.”

A study of immigrant Indian women in the United States who had tried to learn their unborn babies’ gender, published in 2011 by Sunita Puri and three other researchers, found “that 40 percent of the women interviewed had terminated prior pregnancies with female fetuses and that 89 percent of women carrying female fetuses in their current pregnancy pursued an abortion.”

According to Puri, “One-third of women described past physical abuse and neglect related specifically to their failing to produce a male child. The most common forms of neglect were the withholding of food, water, and rest during a woman’s pregnancy with a female fetus, although women also described being hit, pushed, choked, and kicked in the abdomen in a husband’s attempt to forcibly terminate a pregnancy. Some women reported that they were denied prenatal care if the fetus had been identified as female, and four women reported that their families either did not take them to the hospital when they were in labor with a female child or pick them up after delivery.”

It is inconceivable to me how our Nobel Prize-winning President utterly refuses to protect little girls from the violence of sex-selection abortion.

U.S. Rep. Christopher Smith, a Republican, represents New Jersey’s 4th District in the U.S. House. He is a co-sponsor of the Prenatal Nondiscrimination Act.