While the recent project and additional defenses may help keep foreign militants out, it does very little to address the root cause of Saudi troubles: internal radicalization. Saudi citizens continue to be among the highest foreign fighters joining ISIS in the fight in Syria as well as among the highest arrested in local terrorist groups.

Seems like Saudi Arabia is under increasing pressure. From the NYT, a month ago when King Salman announced he wouldn't meet with President Obama:

But administration officials said that the Arab officials had pressed for a defense treaty with the United States pledging to defend them if they came under external attack. But that was always going to be difficult, as such treaties — similar to what the United States has with Japan — must be ratified by Congress.

Instead Mr. Obama is prepared to offer a presidential statement, one administration official said, which is not as binding and which future presidents may not have to honor.

The Arab nations are also angry, officials and experts said, about comments Mr. Obama recently made in an interview with The New York Times, in which he said allies like Saudi Arabia should be worried about internal threats — “populations that, in some cases, are alienated, youth that are underemployed, an ideology that is destructive and nihilistic, and in some cases, just a belief that there are no legitimate political outlets for grievances.”

On one hand, I'm a little confused because both the House of Saud and ISIS are Sunnis, they both have a natural enemy in Iran, I would imagine they would be less adversarial, but I guess the realities are more complex than that. ISIS obviously hates the west for our violent meddling, and the Saudis are stuck in the middle, relying on a tenuous alliance with the US, while we negotiate deals with Iran. Add to that, the murmur about Saudi Arabia's culpability in 9/11, I guess it makes sense that they're feeling a little cagey. The chatter about them buying nuclear weapons from Pakistan seems a little auspicious as well, not to mention the shakeup at Aramco and tightening of royal control over the oil industry.