After Somalia ratified the United Nations Convention on the Rights of the Child (CRC) last week, the United States remains the only UN member country that has not ratified this treaty, which aims to protect the world’s most vulnerable.

Congrats to #Somalia, the 196th nation to ratify the Convention on the Rights of the Child! http://t.co/Qe5H67An5n pic.twitter.com/kGQy16NpPr — UNICEF (@UNICEF) October 3, 2015

The convention entered into force 25 years ago, in September 1990, and since then 196 countries have joined this “most widely ratified international human rights treaty,” as the UN Committee for Human Rights describes the CRC.

The shocking fact is that the US is the sole member of the United Nations that has refused to ratify it.

@BarackObama why has the United States not signed onto the Convention for the Rights of the Child? — Maggie Dimock (@MaggieDimock12) September 28, 2015

Experts list various reasons to explain why the United States continues to hold out. Amnesty International suggests “misconceptions” about the treaty within the US Senate and public opinion.

“Due to widespread misconceptions about the Convention's intent and provisions, and a lack of public understanding about how this type of agreement is implemented by our government, the Convention has encountered a notable level of opposition within the Senate and in the public,” the human rights watchdog states on its US website.

Specifically, a large and influential group of conservative religious organizations, such as the Christian Coalition, Family Research Council, the National Center for Home Education and others, have long been passionately opposed to ratification of the treaty, claiming the CRC undermines parental authority, and usurps national and state sovereignty.

“The Convention would allow and encourage children to sue parents, join gangs, have abortions,” Amnesty reports.

Jo Becker, advocacy director with Human Rights Watch’s Children’s Rights Division, says the US’ failure to ratify reflects unfortunate realities about the conditions faced by youth in the country.

“The main legal challenge for US ratification is that it remains the only country to sentence children to life in prison without the possibility of parole – a punishment the treaty specifically prohibits,” she wrote.

But as Becker describes, the US Supreme Court in recent years has issued several decisions narrowing the application of this sentence to child law offenders.

“The US should ratify the treaty and declare that it is working to end the practice in the states that allow it,” the advocacy director appealed.

Will the US ratify the children's convention, now that every other country has? http://t.co/c80gQt1BC0 pic.twitter.com/pE5KfmWek5 — Jo Becker (@jobeckerhrw) October 2, 2015

The Convention on the Rights of the Child defines children as persons up to the age of 18. All states that have ratified this international treaty are expected to “ensure that all children – without discrimination in any form – benefit from special protection measures and assistance; have access to services such as education and health care; can develop their personalities, abilities and talents to the fullest potential; grow up in an environment of happiness, love and understanding; and are informed about and participate in, achieving their rights in an accessible and active manner,” according to UNICEF.

Out of eighteen international human rights treaties, the US ratified only five.