The U.S. has long been wary of the I.C.C., but relations have been thawing.

The International Criminal Court was created two decades ago as a permanent body to investigate war crimes, genocide and crimes against humanity under a 1998 treaty known as the Rome Statute. In the past, the United Nations Security Council had established ad hoc tribunals to address atrocities in places like the former Yugoslavia and Rwanda.

Many democracies joined the International Criminal Court, including close US allies like Great Britain. But the United States has long kept its distance, worried that the court might one day try to try Americans.

Both the Democratic and Republican administrations have taken the position that the court should not exercise jurisdiction over citizens of countries that are not party to the treaty.

President Bill Clinton signed the Rome Statute in 2000 but, calling it flawed, did not send it to the Senate for ratification. In 2002, President George W. Bush essentially withdrew that signature. Congress, for its part, enacted laws in 1999 and 2002 that limited the support the government could provide to the court.

Even so, at the end of the Bush administration, the State Department declared that the United States accepted the “reality” of the court and acknowledged that “it enjoys great international support.” And the Obama administration took a step to help the court by offering rewards for the capture of the fugitive warlords in Africa whom the court had indicted.

In 2017, however, the court’s chief prosecutor tried to investigate the torture of detainees accused of terrorism during the Bush administration as part of a broader investigation into the war in Afghanistan. In response, the Trump administration imposed sanctions on court staff, and Secretary of State Mike Pompeo denounced them as corrupt.

A thaw in relations returned in 2021, when the Biden administration revoked President Trump’s sanctions and a newly appointed prosecutor, Karim AA Khan, abandoned the investigation.

Then Russia invaded Ukraine last year, sparking a bipartisan push to hold Russia’s President Vladimir V. Putin and others in his military chain of command to account for the reported atrocities, and prompting debates within the administration and elsewhere. Congress on whether and how to help. Court.

In late December, Congress included a provision on the International Criminal Court embedded in the large appropriations bill It happened at the end of December.

It created an exception to the blanket ban on providing certain funds and other assistance to the court, allowing the government to assist with “investigations and prosecutions of foreign nationals related to the situation in Ukraine, including support for victims and witnesses.”