The general base duty rate the US applies to imports from normal-trade-relations countries.
The Most Favored Nation rate — labeled "Column 1 General" on the tariff schedule — is the standard duty rate the United States applies to imports from any country it has normal trade relations with, absent a specific trade-remedy action or preference program. Despite the name, it is not a special or preferential rate; it is the baseline. Trade-remedy programs like Section 301 and Section 232, and preference programs like USMCA, are layered on top of (or, for USMCA, potentially replace) the MFN rate — they do not redefine it.
HTSUS Column 1 General, set under normal-trade-relations (formerly "most-favored-nation") status, 19 U.S.C. 2136.
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