While the United States has fairly open trade policies, there are some import restrictions. In most instances, importing items in restricted categories isn't entirely prohibited. Instead, regulations, limitations or warnings may apply. Shipping alcohol, for example, may be subject to limitations depending on the state of delivery, while shipping cultural artefacts requires a clear declaration of legal ownership.
Both military and biological shipments must have licensing from the proper US agency in order to be imported legally. Some items cannot be imported at all, including cat and dog fur, drugs and paraphernalia, and endangered animals. There are also restrictions and prohibitions on food items. For more information on the specific restrictions in all categories, see the official United States' guidelines.
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