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　　Four times in the past 18 months, China has carriedout hypersonic weapons tests. Hypersonic weapondelivery vehicles can travel at speeds of more thanfive times the speed of sound. China says its mostrecent test flight was on June 9th. The tests are asign of the country's continuing efforts to makehighly developed weapons.

　　The hypersonic missile delivery vehicles are able totransport nuclear weapons. But China said the testsare, in its words, "purely scientific and (are) nottargeted at any country."

　　The United States, Russia and India have also been developing hypersonic vehicles.

　　One of China's four tests reportedly failed. And the United States is far ahead of the Chinese inmissile development. But China is developing hypersonic capability and could one day havebetter delivery vehicles than the United States. So says James Acton of the Nuclear PolicyProgram and the Carnegie Endowment for International Peace. He spoke recently to membersof the U.S. Congress.

　　Mr. Acton said China's hypersonic weapons development program is probably less developedthan the American program. But he said China might be able to develop its program morequickly.

　　The U.S. military has been testing hypersonic weapon delivery vehicles for the past five years.The military completed a fourth successful test two years ago. Some experts say hypersonicglide vehicles could be available for use by the armed forces within five to 10 years.

　　Morley Stone is Chief Technology Officer for the U.S. Air Force Research Laboratory. He said themilitary will continue to develop its hypersonic capability. He said the military knows it isgoing to need weapons that can travel faster than those deployed by other countries. He saysthe U.S. must continue its research efforts.

　　Mr. Acton agrees that the United States has a more-advanced hypersonic weapons program.But he thinks China's hypersonic weapons are still a serious threat to the U.S. because there isno way to defend large areas against them.

　　In recent years, U.S. lawmakers expressed concern about China's development of hypersonictechnologies. Some said that the United States is falling behind China in the hypersonic armsrace.

　　Buck McKeon of California was a member of the House of Representatives until early this year.He also served as chairman of the House Armed Services Committee. He and two othermembers of the committee released a statement after China's first test of hypersonic vehicleslast year. The statement said cuts in military spending have hurt America's technologicaladvantage. It said the Chinese and other nations are seeking to become as powerful militarilyas the United States. "In some cases," it added, "they appear to be leaping ahead of us."

　　American officials hope the United States can keep its lead in being able to launch targetedmissile strikes quickly. They say such a lead can persuade possible enemies from launchingattacks.

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