can result from global exigencies that emerge abruptly and force themselves on national policy agendas (as with international terrorism, examined by Sandler) or emerge more gradually (as with taxation of the income earned by mobile factors of production, at the center of Musgrave’s chapter).The analyses show that the incentives of states to move from acting unilaterally to cooperating with other states vary with the issue and with the power of states to shape the international policy dialogue.