The first source of uncertainty is the recasting of the relationship between S&T and US national security.

A second source of uncertainty is the duration, depth, and eventual effects of the current worldwide economic weakness.

A third source of uncertainty is the effect of the continuing globalization of labor markets on the US knowledge-based economy.

The dynamics of skilled labor migration in the context of changing government and industry policies are hard to predict.

A range of indicators traces a trend that shows growing competitive strength in the Asian region outside of Japan, chiefly in China, South Korea, Malaysia, Singapore, and Taiwan. They have in place, or are instituting, policies and incentives to retain their highly trained personnel, attract expatriates, or otherwise benefit from their nationals working abroad, chiefly in the United States.