Question

US entry into the war marked a new phase that proved costly to the Vietnam , as well as the Americans . Explain

Answer 1

here is u r answer
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when the us inter in war then the phase proved costly because the American soldiers used heavy military equipment .the Vietnam save to our citizen and attack on military of America.Vietnam have not well prepared to war but the military of Vietnam well prepared .it's cost of Vietnam more costly to buying equipment.
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