Changes in the domestic politics of East-West energy trade policy indicate a more general transformation of the domestic politics of American foreign policy. In the postwar period the basic, consensual pattern of congressional bipartisanship, executivebranch unity, interest-group collaboration, and a supportive public has been replaced by the conflictual pattern of an assertive Congress, a fragmented executive branch, antagonistic interest groups, and a divided public. These contrasting patterns are manifestations of structural changes in the domestic political economy. Along both political and economic dimensions, and differentiated according to whether the locus of pressure was group-specific or more general, what had been basic foundations of consensus became by the early 1970s fissures of conflict. Of particular significance were the weakening of the macropolitical foundations (the basic accord on foreignpolicy objectives and strategies) in the wake of both Vietnam and detente and the increased marginal value of the economic costs, both diffuse (macroeconomic) and particularistic (microeconomic), to be paid for economic coercion. In this transformed context, the state's support-building instruments of ideology and economic compensation were insufficient to build consensus. As a result, in this issue area and perhaps more generally, high levels of domestic constraints on the conduct of American foreign policy have become the rule rather than the exception.