322 WORLD POLITICS frustrated,while that of the more advanced ones would be enhanced. A more open structure would leave the less developed states in a polit- ically more vulnerable position,because their greater factor rigidity would mean a higher relative cost of closure.Because of these disad- vantages,large but relatively less developed states are unlikely to accept an open trading structure.More advanced states cannot,unless they are militarily much more powerful,force large backward countries to accept openness. Finally,let us consider a hegemonic system-one in which there is a single state that is much larger and relatively more advanced than its trading partners.The costs and benefits of openness are not sym- metrical for all members of the system.The hegemonic state will have a preference for an open structure.Such a structure increases its ag- gregate national income.It also increases its rate of growth during its ascendency-that is,when its relative size and technological lead are increasing.Further,an open structure increases its political power,since the opportunity costs of closure are least for a large and developed state. The social instability resulting from exposure to the international sys- tem is mitigated by the hegemonic power's relatively low level of involvement in the international economy,and the mobility of its factors. What of the other members of a hegemonic system?Small states are likely to opt for openness because the advantages in terms of ag- gregate income and growth are so great,and their political power is bound to be restricted regardless of what they do.The reaction of medium-size states is hard to predict;it depends at least in part on the way in which the hegemonic power utilizes its resources.The potentially dominant state has symbolic,economic,and military capa- bilities that can be used to entice or compel others to accept an open trading structure. At the symbolic level,the hegemonic state stands as an example of how economic development can be achieved.Its policies may be emu- lated,even if they are inappropriate for other states.Where there are very dramatic asymmetries,military power can be used to coerce weaker states into an open structure.Force is not,however,a very efficient means for changing economic policies,and it is unlikely to be employed against medium-size states. Most importantly,the hegemonic state can use its economic resources to create an open structure.In terms of positive incentives,it can offer access to its large domestic market and to its relatively cheap exports. In terms of negative ones,it can withhold foreign grants and engage322 WORLD POLITICS frustrated, while that of the more advanced ones would be enhanced. A more open structure would leave the less developed states in a polit￾ically more vulnerable position, because their greater factor rigidity would mean a higher relative cost of closure. Because of these disad￾vantages, large but relatively less developed states are unlikely to accept an open trading structure. More advanced states cannot, unless they are militarily much more powerful, force large backward countries to accept openness. Finally, let us consider a hegemonic system-one in which there is a single state that is much larger and relatively more advanced than its trading partners. The costs and benefits of openness are not sym￾metrical for all members of the system. The hegemonic state will have a preference for an open structure. Such a structure increases its ag￾gregate national income. It also increases its rate of growth during its ascendency-that is, when its relative size and technological lead are increasing. Further, an open structure increases its political power, since the opportunity costs of closure are least for a large and developed state. The social instability resulting from exposure to the international sys￾tem is mitigated by the hegemonic power's relatively low level of involvement in the international economy, and the mobility of its factors. What of the other members of a hegemonic system? Small states are likely to opt for openness because the advantages in terms of ag￾gregate income and growth are so great, and their political power is bound to be restricted regardless of what they do. The reaction of medium-size states is hard to predict; it depends at least in part on the way in which the hegemonic power utilizes its resources. The potentially dominant state has symbolic, economic, and military capa￾bilities that can be used to entice or compel others to accept an open trading structure. At the symbolic level, the hegemonic state stands as an example of how economic development can be achieved. Its policies may be emu￾lated, even if they are inappropriate for other states. Where there are very dramatic asymmetries, military power can be used to coerce weaker states into an open structure. Force is not, however, a very efficient means for changing economic policies, and it is unlikely to be employed against medium-size states. Most importantly, the hegemonic state can use its economic resources to create an open structure. In terms of positive incentives, it can offer access to its large domestic market and to its relatively cheap exports. In terms of negative ones, it can withhold foreign grants and engage