On 2 April 2025,
President Trump signed an Executive Order to impose so-called reciprocal
tariffs on imports from about ninety nations, and the tariffs range between 10%
and 50%. A global trade war is brewing on account of the reciprocal tariffs by
the US. The US reciprocal tariffs bring various issues such as whether it
violates most-favoured-nation (MFN) treatment of the WTO regime, whether they
fall within the exceptions to MFN treatment. This paper reviews whether the US
reciprocal tariffs are covered by the MFN treatment of the WTO regime and are
in conformity with the MFN treatment. This paper also reviews whether the US
reciprocal tariffs fall within the exceptions to MFN treatment, in particular,
the national security exceptions.