US President George W. Bush on Tuesday defended the administration's plans for an anti-missile system and accused those opposed to the program of not understanding the threats of the 21st century.

In a speech at a Boeing Co. plant near Philadelphia, Pennsylvania, Bush said those "who oppose this ballistic missile system don't understand the threats of the 21st century."

Opponents of the system were "living in the past. We're living in the future. We're going to do what's necessary to protect this country," he said.

Bush noted in his speech that Boeing was a major contractor on the project, and Boeing engineers last month loaded the first missile interceptor into a silo in Alaska.

This was Bush's 32nd visit to Pennsylvania, a state with 21 electoral voters that he lost in the 2000 elections.

The US military deployed a ground-based missile interceptor last month in Alaska, the first of a national defense system designed to shoot down enemy missiles, and by the end of the year,would install five more interceptors in Alaska and four in California.

Bush has approved 10 billion US dollars for the project in fiscal 2005. The Missile Defense Agency estimated the system would cost as high as 53 billion dollars for 2004-2009.

Source: Xinhua