494. Canada and Mexico also each conditionally appeals the Panel's exercise of judicial economy with respect to whether the COOL measure nullifies and impairs benefits within the meaning of Article XXIII:1(b) of the GATT 1994. Canada further raises a conditional appeal with respect to the Vilsack letter. That is, should we reverse the Panel's finding of inconsistency under Article 2.1 of the TBT Agreement, and not find the COOL measure to be inconsistent with Article III:4 of the GATT 1994, then Canada requests us to complete the legal analysis under Article XXIII:1(b) and to find that both the COOL measure and the Vilsack letter nullify and impair benefits accruing to Canada under successive multilateral trade negotiations. Should those same conditions be satisfied, then Mexico requests us to complete the legal analysis under Article XXIII:1(b) and to find that the COOL measure nullifies and impairs benefits accruing to Mexico from the tariff concessions made by the United States in its tariff bindings.

495. Having upheld the Panel's finding that the COOL measure is inconsistent with Article 2.1 of the TBT Agreement, the first condition upon which Canada's and Mexico's appeals under Article XXIII:1(b) of the GATT 1994 are made is not met, and we therefore need not make any findings in respect of Article XXIII:1(b) with regard to the COOL measure. It is also unnecessary for us to make any finding with regard to the Vilsack letter.