The reason why trade barriers is being used when the us refuses to trade with another country is: Upholding standards.
Upholding standard is the process were a country tend to follow and maintain their set standard without deviating from it.
United states refuse to trade with others country because other country were using children as a laborer to produce goods and United state is against it leading to what is called trade barrier.
Inconclusion the reason why trade barriers is being used when the us refuses to trade with another country is: Upholding standards.
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