The Pentagon is building its own Internet to give all American commanders and troops a moving picture of all foreign enemies and threats.

"This Internet in the sky would allow marines in a Humvee (a military vehicle) in a faraway land, in the middle of a rainstorm, to open their laptops, request imagery" from a spy satellite, and "get it downloaded within seconds," Peter Teets, undersecretary of the air force, told Congress.

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The Pentagon calls its secure network the Global Information Grid or GIG. The network was conceived six years ago and the first connections were laid six weeks ago. It is expected to take two decades and hundreds of billions of dollars to build the new war net and its components. While critics say the cost will be staggering, advocates of the project say networked computers will be the most powerful weapon in the American arsenal.