Fears of rogue states, withdrawal of cold war-era security guarantees, a falling technological threshold, and availability to terrorist organizations ensure that nuclear weapons proliferation remains a central security issue and that developing an adequate theory of proliferation ranks high on the agenda. A data set on nuclear proliferation is constructed that identifies three different stages on the path to the weaponization of nuclear weapons technology. Hazard models and multinomial logit are used to test theories of nuclear proliferation. Results suggest that nuclear weapons proliferation is strongly associated with the level of economic development, the external threat environment, lack of great-power security guarantees, and a low level of integration in the world economy.Sincetheadventoftheatomicage,nuclearweapons proliferation has been one of the major security issues facing the world. After the end of the cold war, concerns about proliferation have grown rather than subsided: the withdrawal of superpower security guarantees has created incentives for smaller powers to acquire nuclear weapons, a handful of "rogue" states have sought nuclear arms, Pakistan and India have joined the ranks of overt nuclear powers, the technological threshold necessary to develop atomic weapons is in reach of ever more nations, and the possibility of new nuclear powers selling weapons to terrorist organizations has focused concerns. Controversy rages around the world over U.S. plans to build a national missile defense (NMD) system to fend off emerging nuclear threats, and scholars debate whether NMD will fan the fires of proliferation or reduce the incentive for more states to acquire nuclear 859 AUTHORS' NOTE: Thanks to

Through a pooled cross-section time-series analysis of the determinants of wage inequality in sixteen OECD countries from 1973 to 1995, we explore how political-institutional variables affect the upper and lower halves of the wage distribution. Our regression results indicate that unionization, centralization of wage bargaining and public-sector employment primarily affect the distribution of wages by boosting the relative position of unskilled workers, while the egalitarian effects of Left government operate at the upper end of the wage hierarchy, holding back the wage growth of well-paid workers. Further analysis shows that the differential effects of government partisanship are contingent on wage-bargaining centralization: in decentralized bargaining systems, Left government is associated with compression of both halves of the wage distribution

What accounts for the apparent breakdown of the positive relationship between powerful trade union organizations and macroeconomic performance? Is corporatism a relic of a different age, a luxury of the long postwar boom? Although the authors answer the latter question in the negative, they do contend that existing arguments about the macroeconomic consequences of corporatism should be significantly modified to take into account the impact of the growth of public sector unions on the relationship between institutional structure of labor movements and economic outcomes. The deteriorating performance commonly attributed to corporatism in the 1980s was limited to countries in which unions in the public sector and other sectors not exposed to international competition increasingly dominated national labor movements. Encompassing trade union movements can still generate wage restraint, but only where the union movement is dominated by unions in the exposed sector that are subject to the constraints posed by international market competition.

Study after study has found that regime type has little or no effect on states' decisions to pursue nuclear weapons. We argue, however, that conventional approaches comparing the behavior of democracies to that of nondemocracies have resulted in incorrect inferences. We disaggregate types of nondemocracies and argue that leaders of highly centralized, "personalistic" dictatorships are particularly likely to view nuclear weapons as an attractive solution to their concerns about regime security and face fewer constraints in pursuing nuclear weapons than leaders of other types of regimes. Combining our more nuanced classification of regime type with a more theoretically appropriate empirical approach, we find that personalist regimes are substantially more likely to pursue nuclear weapons than other regime types. This finding is robust to different codings of proliferation dates and a range of modeling approaches and specifications and has significant implications for both theory and policy.

for helpful comments and suggestions.