President Barack Obama will leave office having failed to use the tools at his disposal to make significant progress on getting child soldiers off the battlefield. That is the consensus among human rights groups who point out that for six consecutive years, the Obama Administration has subverted American law requiring the president to sanction foreign governments that force children to fight.

As early as this week, the administration will announce for the final time a list of waivers and exemptions to the Child Soldiers Protection Act, a law passed in 2008 that forbids the United States from giving military aid to any foreign government that systematically uses children in its armed forces. According to officials involved in the process, the president will either fully or partially waive sanctions for every abuser country that receives US military assistance.

It is a familiar pattern the president has followed each year since 2010, the first year he was required to sanction abuser countries under the law. The Obama Administration has given more than $1.2 billion in military assistance and arms to governments that use child soldiers since the law was enacted and withheld only $61 million, according to the Stimson Centre. The President’s final decision on waiving sanctions under the law is due on Saturday.

“This is Obama’s last chance to get it right,” said Jo Becker, advocacy director of the children’s rights division at Human Rights Watch.

In a September 14 letter, several advocacy groups urged Obama to use the law in his final year to help to end the practice.

Administration officials say no final decisions have been made, but that after an inter-agency process, Obama is expected to fully or partially waive sanctions for Burma, the Democratic Republic of Congo, Iraq, Nigeria, Somalia and South Sudan, all under the justification of “national interest”. Waivers are not required for the other countries identified by the State Department’s own reporting on human trafficking as using child soldiers because they do not receive US military aid. These are Sudan, Syria and Yemen. The child advocacy community finds South Sudan to be a particularly egregious example, as that government, which is slated to receive $30 million in US assistance related to peacekeeping operations in 2017, has drastically increased recruitment of child soldiers amid a deepening crisis, often conscripting them by force.

Administration officials have repeatedly used partial waivers for South Sudan, and the president will issue another one this year, an administration official said. The leeway is meant to allow support for peacekeeping to continue and to maintain some leverage and influence with a government that the US has long supported.

“We are not seeing change,” said Rachel Stohl, senior associate at the Stimson Centre. “There’s no evidence partial waivers have worked to change South Sudan’s poor behaviour and impunity.”

Afghanistan, where there was also a rise in the use of child soldiers this year, was not even included on this year’s list of countries eligible to be sanctioned. The State Department’s legal office made an unprecedented and highly controversial ruling that, because the abuses occur largely in the Afghan National Police, rather than in the army, the practice does not meet the legal definition of “armed forces” under the law.

“They did bureaucratic somersaults to claim that the groups using child soldiers in Afghanistan are not government-supported groups,” Stohl said.

Supporters of the administration point to some limited successes in the effort to pressure countries to demobilise child soldiers. Ben Marter, a spokesman for Richard J. Durbin, the Democratic senator from Illinois, one of the law’s original champions, said waivers have led to positive government action in Chad. Other officials also point to Congo, which has greatly reduced its use of child soldiers.

There are also distinctions made between types of military aid. For example, waivers are often issued for aid used to train foreign military officers because such training can be valuable to the effort to professionalise these militaries and to build constructive relationships. Aid is also seen by the administration as a carrot to be dangled; Burma does not receive direct military assistance but will get a full waiver this year as a signal that the US has not ruled out the idea. Still, even supporters of limited waivers believe the administration has gone too far. “There are some habitual violators that at some point seem no longer worthy of this approach,” Marter said. When the administration announces its final list of waivers, it will cement the President’s shameful legacy on child soldiers. In his narrow construction of US “national interest”, Obama has undermined Congress’s efforts and missed his opportunity to significantly help the vulnerable victims of this abhorrent practice.

• Josh Rogin is a columnist for the Global Opinions section of The Washington Post. He writes about foreign policy and national security