Russia – Measures concerning Traffic in Transit (DS512) is the very first case in which a WTO panel interpreted and applied GATT Art. XXI. When the Crimean Crisis in 2014 broke out, Russia introduced a series of requirements and prohibitions on all road and rail transit and certain products from Ukraine destined for the Republic of Kazakhstan or the Kyrgyz Republic. The WTO panel eventually found that the measures in question are consistent with GATT Art. XXI(b)(iii) (security exception). The panel, on the other hand, opined that the article is not totally self-judging, and that any decision under the article by an invoking member (in this case, Russia) must be subject to a combination of objective and good faith reviews conducted by a panel, despite the objection to this interpretation by two of the superpowers, i.e., Russia as a complained party, and the United States as a third country. Since President Trump took office in the United States, an increasing number of trade measures have been introduced, allegedly for security purposes, and trade and security issues have become remarkably intertwined. In particular, in the context of the United States' tariff increase on steel and aluminum products under Section 232, and Japan's reinforcement of export control on exports to Korea, applicability of GATT Art. XXI is controversial. This precedent will have significant implications for these subsequent cases.