The Pentagon is spending billions of dollars on new forms of space warfare to counter the growing risk of missile attack from rogue states and the "satellite killer" capabilities of China.

China is starting to ramp up its scramjet propulsion work -- an initiative that will benefit high-speed missile programs. Over the next several decades, the scramjet work could eventually provide China with a tactical hypersonic global-strike capability beyond the country's strategic ballistic missile force. The U.S. has similar goals for its own growing scramjet program.

The Pentagon is working to develop a suborbital space capsule within the next five years that would be launched from the United States and could deliver conventional weapons anywhere in the world within two hours, defense officials said.

NASA's X-43A scramjet programme successfully smashed its own world speed record for aircraft by flying at nearly 10 times the speed of sound. While future funding for NASA research on hypersonic flight is uncertain, the test demonstrates the potential of hypersonic flight for other military applications.

The author looks at the military motivations behind the development of the X-34 hypersonic aircraft and warns that the test could herald a new era of warfare and a new space race between the U.S. and Russia.

The Pentagon is planning a new, more lethal, remotely operated aircraft that could bomb targets anywhere on Earth within a scant two hours of taking off from the United States.

The US military has begun development of an ultra-high speed weapons system that would enable targets virtually anywhere on Earth to be hit within two hours of launch from the continental US.

The author looks at several space weapons systems currently under consideration by the U.S. including kinetic-energy weapons, hypersonic planes, and space lasers.

The Defense Department wants to develop a high-speed drone able to launch attacks anywhere in the world within two hours of leaving a U.S. base.

The Pentagon is planning a new generation of weapons, including huge hypersonic drones and bombs dropped from space, that will allow the US to strike its enemies at lightning speed from its own territory.