(Newser) – North Korea's threats to hit US targets in the Pacific might well be hot air, but the Pentagon says it has no choice but to take them seriously. As a result, it plans to move a high-tech missile-defense system to Guam to protect military bases in the area, reports the BBC and Wall Street Journal. This will mark the first global deployment of the Terminal High Altitude Area Defense system, or THAAD, and it comes two years ahead of schedule.

The Pentagon describes it as a "precautionary move" and offered no details about when it might take place. It's no small feat: One THAAD battery costs $800 million and consists of interceptor missiles ($1 million apiece), a truck to launch them, and a sophisticated radar system to guide the way. "Some of the actions they've taken over the last few weeks, present a real and clear danger," US defense chief Chuck Hagel said today of Pyongyang. (Read more THAAD stories.)

