The Pentagon has proposed upgrading the newest GPS satellites which have not yet been launched. The upgrade would allow the satellites to put out a signal eight times stronger than what they can currently produce.
The boosted signals would be available only for military use, however, to avoid what Donald Rumsfeld terms "a space Pearl Harbor." The GPS devices used by civilians would not be affected, nor would over-the-counter GPS locators used by foreign militaries. These devices would continue to receive the low-power transmissions, leaving them vulnerable to jamming. This would also allow the U.S. military to jam an enemy's GPS receiver while still using its own.
The Bush administration is seeking $50 million of the total $200 million it would ultimately cost for the project in its 2003 budget.