The US is lobbing fresh sanctions against North Korea as a response to the cyber attack on Sony Pictures Entertainment even as President Barack Obama's administration refuses to provide evidence of Pyongyang's involvement.
China may have the ability to remotely shut down computer systems of US power utilities, aviation networks and financial companies, according to director of the US National Security Agency Mike Rogers.
Testifying to the House of Representatives Intelligence Committee on cyber threats, Rogers said digital attackers have been able to penetrate such systems and perform "reconnaissance" missions to determine how the networks are put together.
Chinese hackers have attacked the US weather satellite network, causing services to be sealed off for a period.
The US regularly accuses China of state sponsored assaults on its businesses, industries and utilities.
The US is currently talking of a cooling in trade hostilities that would ensure the smooth passage of technology sales, but the cyber attack allegations still keep coming. The Washington Post reported that the weather satellite attacks happened in September, but were not revealed until late October.
Cyber security is an irritant to bilateral ties. On Wednesday the U.S. Federal Bureau of Investigation said hackers it believed were backed by the Chinese government had launched more attacks on U.S. companies, a charge China rejected as unfounded.
In May, the United States charged five Chinese military officers with hacking American firms, prompting China to shut down a bilateral working group on cyber security.
Job interviews missed, work and wedding plans disrupted, children unable to fly home with their adoptive parents -- the consequences keep proliferating in the aftermath of a database outage that crippled the US State Department's process for issuing passports, visas, and other documents related to travel to the US.