Quotes of the Day

The brutal execution last week of Paul Johnson Jr., an employee of Lockheed Martin who had been living in Saudi Arabia for more than a decade, was a troubling sign of how freely al-Qaeda continues to operate in the kingdom — and of the deadly threats facing the many foreigners (including 35,000 Americans) who live there. But many believe that the atrocity may finally spur the Saudi government to take more aggressive action against extremists. Johnson's murder was the latest in a rash of seemingly coordinated attacks that have killed 24 foreigners in the past month. Responsibility for the terror spree was claimed by Abdulaziz al-Muqrin, 31, believed to be al-Qaeda's chief in Saudi Arabia. Saudi officials said that hours after photos of Johnson's corpse were posted on an extremist website, Saudi security forces tracked down and killed al-Muqrin in a Riyadh suburb. According to the officials, government forces moved in after receiving a tip from a Saudi who saw al-Muqrin driving through the residential neighborhood.

Nowhere does anxiety about al-Qaeda run higher than in the Saudi royal family. The Saudis need the expertise of Westerners to help develop the country's oil sector and attract investment. The latest violence could drive more of them away. The U.S. embassy has recommended that all Americans leave the kingdom. Many of those who are staying say they are growing beards and donning local robes to hide their identities. As for the Saudi leaders, a U.S. official says they do not yet face a direct threat to their rule. But, he says, "there could be a long period of violence that is almost impossible to defend against."

• Scott MacLeod; Hassan Fattah