United States President George W. Bush is expected to issue a directive in the next few weeks. It will give the US Air Force a green light for the development of space weapons, US media reported last week. This would potentially start a new global arms race, some experts have warned. To keep that from happening, last Wednesday the White House explained that it was not considering putting weapons in space. It said it was making a shift in US space policy to allow for protection of satellites. But some defense analysts and arms control advocates argue that the policy will pave the way for the US to put both defensive and offensive  weapons in space. "No one should be fooled," said Theresa Hitchens, an American weapons expert. The US is now restricted by a 1996 directive  signed by President Bill Clinton. Plans for space weapons were vetoed by the Clinton cabinet. The directive emphasized the peaceful use of space , in agreement with almost unanimous global opinion. The US military has placed importance on space and has sent up numberous satellites for troop communications and to provide intelligence and data to guide bombs to their targets. The US Air Force wants to develop space- based weapons that could strike targets anywhere in the world within 90 minutes of receiving the order to open fire. These new weapons under development cover a wide range. They include hunter- killer satellites and orbiting weapons. And they use lasers, radio waves, or even dense metal tubes, known as " Rods from God", dropped from space to do the damage. There are many barriers to the setting up of this kind of program, experts say. First is the coast. It is estimated that the budget may be US $220 billion to US $ 1 trillion . The technical difficulties of developing reliable space weapons are also a problem. And, the program will draw strong criticism from around the world. Experts worry about starting a space arms race. The author's attitude towards the coming space weapon development is   _  .
optimistic critical excited indifferent