An axiom of global trade talks, the “bicycle theory of trade liberalization,” holds that momentum toward freer trade must be constantly maintained to keep protectionism at bay. The bicycle of the post-1930 trading system was built for two, the United States and, first, Great Britain, then the European Community (EC), as significant trade liberalization has happened only when both riders pedaled in tandem. Yet the trading bicycle has never sustained a steady speed, intermittently accelerating, slowing, and idling (though without toppling, as the bicycle theory warns).

This stop–go pace of trade liberalization is a puzzle for international political economy, whose core concepts—for example, hegemony, institutions, ideas, factor endowments—explain shifts from one steady state to another better than they do deviations around a trend. Protection for Exporters, however, investigates these fits and starts from the U.S. side of the transatlantic trading relationship. Its inquiry spans 80 years apportioned into six cases, each covering at least one major trade agreement: the U.S.-British reciprocal trade agreement (RTAA) of 1938 and the General Agreement on Tariffs and Trade (GATT); the second, third, and fourth GATT rounds; the Dillon and Kennedy Rounds; the Tokyo Round; the Uruguay Round; and the still-ongoing Doha Round. In these cases, Andreas Dür finds unexplained variation in the depth of trade liberalization, the trade strategies of the United States, and the balance of concessions on each side of the Atlantic.

The book's central claim is that trade discrimination raises U.S. eagerness to conclude trade agreements and conditions the terms of these deals once made. One part of the argument is domestic: Dür posits that “exporters lobby more against losses than in favor of gains of foreign market access” (p. 3). When the pain of lost trade mobilizes exporters to seek restitution, governments become more sensitive to export interests. There are a variety of means to recapture markets—states can negotiate with the foreign trading bloc, make retaliatory threats, or form a rival agreement—and economy-wide export vulnerability shapes choices among these options. The argument's other part considers interstate bargaining. Trade discrimination enhances a trading bloc's leverage over others, the more so the greater the discrimination and the more vulnerable the excluded countries. This newfound bargaining power motivates trading blocs to negotiate with outsiders, while exporter mobilization encourages excluded countries to reach a trade agreement, even if they have to give more liberalization than they get.

Importantly, this argument illuminates a causal motor, the negative externalities of foreign discrimination, which drives trade liberalization between periods of inactivity through the pursuit of “protection for exporters.” Building from propositions by Kenneth Oye and Richard Baldwin on how trade diversion affects outsiders, Dür suggests that external developments shift domestic interests, pushing governments to find a new optimum in trade policy. Applied to U.S. trade policy, this framework neatly corrects delegation theories, which attribute exporter mobilization to the institutional incentives of the RTAA. Instead, Dür shows, exporters mobilized two years before the RTAA in reaction to British imperial preference. In the decade after 1947, exporter pressure failed to materialize despite repeated RTAA renewals. Yet when the formation of the EC in 1957 triggered a new bout of trade diversion, exporters reemerged in full force.

Another merit is the analytical framework's attention to bargaining outcomes when policies abroad harm a country's exporters. Trade liberalization is frequently negotiated and reciprocal, but it is difficult to integrate domestic and strategic factors into a single model. Dür explains trade bargaining through the concept of export vulnerability, operationalized as a country's trade balance, the size of its export sector, and the geographic distribution of its trade. Vulnerable countries, he reasons, cannot credibly threaten to retaliate or form a rival agreement, leaving fewer alternatives to a one-sided deal with trading blocs that exclude them, while less vulnerable countries are better positioned to extract a fairer balance of concessions. Although vulnerability undoubtedly is relative (without accounting for the vulnerability of both sides, it is impossible to know which will get the best deal), this is still a fuller picture of trade policy than approaches that disregard one or the other level of analysis.

While the book's main arguments are creative and plausible, its empirical tests leave both open to question. If the exporter mobilization claim is right, then at any given time exporters that lost more trade should lobby more than exporters that lost less trade; across time, exporter lobbying should gain intensity after trade is lost. Yet industry-level data to validate these propositions are absent, and the abundance of available evidence is too much for process tracing alone to handle. As a result, the case studies establish that some exporters mobilized, but not that mobilization and lost trade are correlated for industry cross sections or over time. Without disaggregated trade flows and informative data snapshots in the tables on industry lobbying (if not a quantitative test), it is hard to tell whether lost trade explains mobilization better than the time-tested alternative hypothesis that overall, export dependence drives lobbying.

The indicators of export vulnerability also are measurable with ample data. Some figures appear selectively in the narrative and point inconveniently in opposite directions. This undermines faith in Dür's contention that the United States was more vulnerable to trade discrimination when it had a trade surplus and a smaller export sector in 1938, 1947, and 1957, but less vulnerable when it had a trade deficit and a larger export sector in 1979 and 1993. A look beyond transatlantic trade to Germany in the 1930s, Great Britain, or other European countries excluded from the original EC, or to Japan's response to the Single Market Program and the North American Free Trade Agreement, might have helped to clear up these uncertainties.

The argument's strongest case is probably the Kennedy Round, which achieved sizable tariff cuts on the heels of the EC's formation. Weighed against the lull in the GATT rounds of the 1950s, Dür persuasively argues that the alarm U.S. exporters felt about trade diversion in Europe propelled John F. Kennedy's trade initiative. The RTAA with Great Britain also stands up well against the evidence, although the claim that exporter lobbying against imperial preference produced the GATT seems a stretch given the depression and war of the intervening 15 years. The Uruguay Round is a tougher case because U.S. exporters could expect free trade with Canada and Mexico to offset some of their losses from the Single Market Program, a problem that is overlooked, yet Dür nevertheless makes a compelling case that deeper European integration mobilized U.S. exporters to promote the launch and conclusion of this trade round.

A rigorous empirical evaluation, together with a wide-ranging review of transatlantic trade relations, a subject that has received “scant scholarly attention” (p. 211), would be ambitious for a book of any length. In a concise 222 pages of text, Dür travels a great distance. Both his detailed account of how European trade discrimination has repeatedly spurred trade liberalization in the United States and his explanation of these regional determinants of multilateralism are worthwhile reading for anyone interested in international political economy and the global trading system.