A recent emphasis on displays of military strength and brinkmanship-style posturing may reflect mounting insecurities among Iran's leadership, experts say. There's certainly no shortage of concerns for Iran's ruling clerics and the powerful Revolutionary Guard force that increasingly directs the country's policies.

Among those concerns: Iran is seriously outgunned. The U.S. has bases throughout the region and the Navy's 5th fleet in Bahrain, has sold $3.48 billion worth of missiles and related technology to the United Arab Emirates, and has announced the sale of $30 billion worth of F-15SA fighter jets to Saudi Arabia.

The Associated Press reports on the story behind Iran's tougher military doctrine.