that although the WTO's consensus governance model provides law-based initial bargaining, trading rounds close through power-based bargaining favoring Europe and the U.S., and may not lead to Pareto improvement. Dispute settlement The WTO's dispute-settlement system "is the result of the evolution of rules, procedures and practices developed over almost half a century under the GATT 1947". In 1994, the WTO members agreed on the Understanding on Rules and Procedures Governing the Settlement of Disputes (DSU) annexed to the "Final Act" signed in Marrakesh in 1994. Dispute settlement is regarded by the WTO as the central pillar of the multilateral trading system, and as a "unique contribution to the stability of the global economy". WTO members have agreed that, if they believe fellow-members are violating trade rules, they will use the multilateral system of settling disputes instead of taking action unilaterally. The operation of the WTO dispute settlement process involves case-specific panels appointed by the Dispute Settlement Body (DSB), the Appellate Body, The Director-General and the WTO Secretariat, arbitrators, and advisory experts. The priority is to settle disputes, preferably through a mutually agreed solution, and provision has been made for the process to be conducted in an efficient and timely manner so that "If a case is adjudicated, it should normally take no more than one year for a panel ruling and no more than 16 months if the case is appealed... If the complainant deems the case urgent, consideration of the case should take even less time. WTO member nations are obliged to accept the process as exclusive and compulsory. According to a 2018 study in the Journal of Politics, states are less likely and slower to enforce WTO violations when the violations affect states in a diffuse manner. This is because states face collective action problems with pursuing litigation: they all expect other states to carry the costs of litigation. A 2016 study in International Studies Quarterly challenges that the WTO dispute settlement system leads to greater increases in trade. However, the dispute settlement system cannot be used to resolve trade disputes that arise from political disagreements. When Qatar requested the establishment of a dispute panel concerning measures imposed by the UAE, other GCC countries and the US were quick to dismiss its request as a political matter, stating that national security issues were political and not appropriate for the WTO dispute system. Accession and membership The process of