2. What are the similarities and the differences between the national treatment obligation in Article III:4 of the GATT 1994 and that in Article 2.1 of the TBT Agreement, as clarified by the Appellate Body in US – Clove Cigarettes (DS406)?

How did the absence in the TBT Agreement of a general exception provision similar to Article XX of the GATT 1994 and the balancing objective set out in the preamble of the TBT Agreement affect the Appellate Body’s interpretation of Article 2.1?