Tuesday's car-bomb attacks on Americans and other foreign workers in Riyadh carry the same message for Saudi Arabia's royal rulers as it does for the US: The tightest security, the best intelligence, and the boldest preemptive strikes aren't enough to root out nimble, networked terrorist cells like Al Qaeda's.
The blasts inside the foreigners' compound - one was delivered in a Chevy Impala - are another wake-up call for Saudi leaders to reform a medieval regime faster than the glacial pace they've been moving, starting with an end to state support for the teaching of Wahhabist Islamic militancy.
The US-led global war on terrorism has an epicenter, and it's not Washington or New York. It's the Saudi capital, home to a conservative monarchy that would still be the prime target for Saudi-born Osama bin Laden even if all 35,000 Americans and other non-Muslim "infidels" left Islam's holiest land. (The blasts came as the US plans to pull out most of its 5,000 troops in Saudi Arabia by this summer, now that Saddam Hussein has fallen.)
Americans are stuck in the middle of what is essentially a civil war - a monarchy vs. Mr. bin Laden's drive for an Islamic state - because of their dependency on the largest oil reserves in the world.
But the burden of protecting Saudi Arabia from either radicals like bin Laden or, as the US has done since the 1991 Gulf War, potential invaders like Iraq, should go hand-in-hand with opening Saudi society to modern education and political liberalism. A constitutional monarchy would be a first step toward channeling the frustration of Saudis away from terrorism and into elections under the protection of civil liberties.
It isn't enough for Saudi security officials to just work hard to uncover threats to Westerners, cooperate with US officials on terrorism, or try to curb charitable donations that find their way to Al Qaeda.
Nor can they simply try to deflect internal criticism of their limited support for the Iraq war by citing their demand that the US act more boldly to resolve the Israeli-Palestinian issue with a "road map."
Saudi Arabia's problem in being both an unwitting exporter of terrorists and the center for regular attacks on expatriate Americans is only a symptom of a deeper inability to emerge as a modern country. And despite its oil wealth, it's unable to create enough desirable jobs for a population that has doubled to 23 million during the past two decades.
These latest attacks on Americans are ultimately an attack on a regime that's failing to move fast enough.