1.   Although close calls are rare and accidents even rarer, safety experts worry that the system is flirting with catastrophe, citing recent near-misses.

2.   Although this is more debatable, some experts also worry that aging will mean less creative and entrepreneurial societies.

3.   And experts worry that resistance to Synercid could develop as well.

4.   And a leading national security expert worries that the growing military involvement in civilian life could have unwanted consequences.

5.   And experts also worry about Pakistan as its joins Russia on the list of nuclear powers with disintegrating economies.

6.   And many experts have worried that large cuts in the shuttle budget are increasing the odds of a fiery disaster.

7.   And some information warfare experts worry as well about the development of weapons that disrupt communications networks with electromagnetic bursts.

8.   Aviation experts worry that there is often too much focus on the last link.

9.   Bioterrorism experts have long worried about nations like Iraq using anthrax on American civilians.

10.   But a few experts worried that the efficiencies might be slow in coming.