The new tariff regime unveiled by the U.S. today represents a stark escalation in trade policy and potentially a structural break from decades of relative tariff stability. The announced rates are at the high end of expectations, and there appears to be little in the way of a mechanism for de-escalation. The proposal is typically unilateral: rather than being contingent on reciprocal trade relations, the tariffs are explicitly cast in terms of bilateral trade imbalances. This is a departure from the rules-based international order under the WTO, in which tariffs are normally multilaterally negotiated and founded on reciprocity.