Is defence spending good or bad for growth?

Global insecurity is obviously rising, which may lead many countries to increase their defence spending. This raises the question of the effect of defence spending on growth: On the one hand, it draws resources and savings away from investment in other activities, which may be highly negative; On the other hand, it can generate positive technological externalities and contribute to developing research, which is positive. Statistical analysis seems to show that there is no significant correlation between defence spending and long-term growth either for OECD countries or emerging countries.