Developed nations should impose carbon border adjustment taxes on imports from countries with weaker climate policies.

This debate on Carbon Border Adjustment Mechanisms (CBAMs) resolved narrowly in favor of the Con position, though the 26% confidence interval indicates a closely contested exchange where both sides demonstrated significant analytical strengths and critical vulnerabilities. The trajectory proved decisive: while Pro established early theoretical coherence regarding carbon leakage prevention, Con gained decisive momentum in Rounds 3 and 4 (7.1 and 7.3 vs. Pro's 6.2 and 6.3) by systematically dismantling Pro's empirical assertions and exposing unaddressed implementation fractures.

Pro's central failing lay in an overreliance on theoretical incentive structures without adequately confronting the practical and legal counter-evidence presented by Con. While Pro effectively articulated the economic logic of internalizing carbon costs to prevent competitiveness losses, their rebuttals increasingly relied on affirming the consequent—assuming that because CBAMs could theoretically drive climate policy convergence, they do in practice without triggering the protectionist retaliations Con documented. Pro's Round 4 concession that Con raised "legitimate concerns" about equity and capacity constraints, while rhetorically disarming, functionally ceded critical terrain; admitting these concerns are legitimate yet claiming they "do not undermine" the policy's necessity created a non sequitur that Con exploited effectively.

Con demonstrated superior engagement with specificity, particularly in Round 3's empirical assault on Pro's "positive incentives" narrative. By citing concrete trade impacts and the methodological impossibilities of embodied carbon accounting across complex supply chains, Con transformed abstract equity concerns into tangible market failures. However, Con occasionally lapsed into hasty generalization, characterizing all CBAM architectures as inherently coercive without fully engaging Pro's revenue recycling proposals that might mitigate developing nation burdens. The decisive factor remained Con's sustained pressure on the CBDR (Common But Differentiated Responsibilities) principle violation—a legal and moral framework that Pro never fully neutralized, relying instead on assertions of WTO compliance that Con effectively challenged through references to unilateralism.