The new breach comes as a newly disclosed part of a classified Defense Science Board report. Back in January, the board released a public version of the report, warning of possible attacks on U.S. defense systems as well as the Defense Department's lack of preparation and protection. And if you look back in 2005, the same group warned U.S. defense officials against buying microchips from China because of trojan horses and spyware — advice the Pentagon eventually took, cutting off Chinese supply in 2011. But in just the last few months, Chinese hackers have gotten to major U.S. news organizations and government agencies. How have the Pentagon's own cybersecurity experts been so far ahead of the Pentagon's actual cybersecurity if China is stealing our war plans — or at least our warplanes? And is there any way to stop it?

Obama has said that the U.S. military would focus on Asia and the Pacific in the coming year — he called it a "vast and complex undertaking" in his big foreign-policy speech on Thursday. "We cannot look back years from now and wonder why we did nothing in the face of real threats to our security and our economy," Obama said in his State of the Union address this year. Except it may be too late for wonder and speeches; Nakashima reports the Chinese cyberspies already have the basic outlines for the following:

The designs included those for the advanced Patriot missile system, known as PAC-3; an Army system for shooting down ballistic missiles, known as the Terminal High Altitude Area Defense, or THAAD; and the Navy's Aegis ballistic-missile defense system. Also identified in the report are vital combat aircraft and ships, including the F/A-18 fighter jet, the V-22 Osprey, the Black Hawk helicopter and the Navy’s new Littoral Combat Ship, which is designed to patrol waters close to shore. Also on the list is the most expensive weapons system ever built — the F-35 Joint Strike Fighter, which is on track to cost about $1.4 trillion.

So while that big Mandiant report from February — the one linking a nondescript building all the way to the PLA and back to critical U.S. infrastructure, the one the Pentagon outright blamed on the Chinese government — might be scary, this is a cyber race to weapons building. And it's got implications for future combat: "You've seen significant improvements in Chinese military capabilities through their willingness to spend, their acquisitions of advanced Russian weapons, and from their cyber-espionage campaign," James A. Lewis, a cyber-policy expert at the Center for Strategic and International Studies, told the Post's Nakashima.

According to a report last weekby the Commission on the Theft of American Intellectual Property, a group headed up by two ex-Obama administration officials (Dennis Blair and Jon Huntsman), hacking costs the U.S. some $300 billion per year. And you know what? China is reportedly responsible for a full 70 percent of that when it comes to corporate IP and theft. But a New York Times editorial over the weekend added an important point of emphasis: "While there are concerns about military-related incursions, the focus of most public discussion surrounds hacking into business and industry." Behind the scenes, then, the Pentagon is doing more than it's saying — and building up a more sophisticated cyber battle plan of our own: Wired's Noah Shachtman has an in-depth report today on the Pentagon's so-called Plan X, "a program that is specifically working towards building the technology infrastructure that would allow cyber offense to move from the world we're in today," as Darpa's director put it.