Such breaches could enable China, national security experts said, to remotely disrupt important facilities in the Indo-Pacific region that in some form support or service US military operations.
"What she endured is unthinkable," Biden said of 4-year-old released hostage Abigail Edan.
The violent killing put a spotlight on the US civil rights cause after his mother, Mamie Till-Bradley, held an open-casket funeral and a photo of her son's badly disfigured body appeared in media.
Luft, a citizen of the United States and Israel, is accused of recruiting and paying a former high-ranking US government official on behalf of principals based in China in 2016.