Just days after touting a trade truce with China , President Trump acknowledged that China is "always watching us." American intelligence agencies say the Chinese have infiltrated parts of the U.S. power grid and water systems. China has also been accused of stealing American intellectual property and Americans' personal information.  "We're a threat to them, too. Many of the things that you say, we do to them," Mr. Trump said. "Look, this is a very competitive world, especially when it comes