choose to undertake more binding commitments in deep agreements that support more trade or opt for weaker commitments and less trade. Second, while our focus here has been on the complementarity between deep trade institutions and trade flows, it could be argued that a high level of trade integration requires some form of political integration for its legitimacy and long‐run sustainability. Indeed, this complementarity between economic and political integration has been at the core of the European project (Padoa‐Schioppa, 1999). In light of this, deeper forms of agreements may be difficult to pursue outside the Union.

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