WASHINGTON, June 12 (Reuters) – Chinese hackers are all but certain to disrupt American critical infrastructure, such as pipelines and railways, in the event of a conflict with the United States, a senior U.S. cybersecurity official said Monday. In comments made during an appearance at the Aspen Institute in Washington, Cybersecurity and Infrastructure Security Agency Director Jen Easterly said Beijing was making major investments in the capability to sabotage U.S. infrastructure. "This, I think, is the real threat that we need to be prepared for, and to focus on, and to build resilience against," she told her audience. She cautioned…