Some misunderstandings are hard to cure.

Well-secured files don't do you much good if you lose them in a fire or hard drive crash.

I favor pocket-sized hard drives that travel between home and office, syncing with computers on both ends.

There is evidence that some of al Qaeda's nuclear efforts over the years met with swindles and false leads.

Scores of armed antigovernment groups, some of them far more radical, have formed or been revived during the Obama years, according to law-enforcement agencies and outside watchdogs.

The CIA now assesses that four nations - Iraq, North Korea, Russia and, to the surprise of some specialists, France - have undeclared samples of the smallpox virus.