"Economic integration can be beneficial for all participating countries. But after a point, further gains from integration can be achieved only by trading off costs in one policy or sector against benefits in another. In this article we explore the relationship between these trade-offs and their political sustainability. We conjecture that a viable policy is politically sustainable when its benefits to citizens are visible to them. In the longer term, the trade-offs which are required to deepen integration become invisible, at which point reversing the process of integration appears to be in the national interest. We conclude that integration needs to be supported with domestic policies that mitigate the costs of integration borne by some groups or sectors."

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