WE ARE THE GREATER THREAT:

[S]audi Arabia and the other Sunni Arab states should not be so singularly obsessed with the danger posed by Shi'ite-led Iran. These states have other internal problems and economic worries to deal with, especially bulging youth populations and the lack of avenues for political expression. The House of Saud is facing a challenge from the militant group Islamic State, which carried out a suicide bombing last week that killed at least 21 worshippers at a Shi'ite mosque in the kingdom's Eastern Province. The Saudi regime must also cope with the long-term consequences of declining revenue due to lower oil prices.

In an interview with the New York Times in early April, Obama warned that U.S. allies like Saudi Arabia should be more worried about internal threats. These states have "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," Obama said, adding: "I think the biggest threats that they face may not be coming from Iran invading. It's going to be from dissatisfaction inside their own countries."

Obama's comments angered the Arab monarchs, including the leaders of Saudi Arabia, the United Arab Emirates and Bahrain, who decided to send lower-level officials to the Camp David summit. But Obama was trying to initiate a difficult conversation with U.S. allies -- a discussion that got drowned out by a focus on who did and didn't make it to the summit.

Saudi Arabia must deal with its "youth bulge": more than half of the country's population of 29 million is under the age of 25. Two-thirds of the population is under 30. Most troubling, the estimated unemployment rate for Saudis aged 15 to 24 is about 30 percent.

While Saudi officials insist that their substantial foreign reserves allow them to withstand a long period of low oil prices -- and potential regional turmoil -- the reserves dropped by $36 billion in March and April alone. (Saudi reserves peaked at around $800 billion in mid 2014; some economists forecast that they could drop to $500 billion in the next two years.) When King Salman ascended to the throne after his brother's death in January, he granted salary bonuses to all public employees and members of the military. Those bonuses most likely came out of the foreign reserves, since the kingdom was already projecting a 2015 budget deficit of $40 billion -- the first in seven years. The Saudi-led war against Houthi rebels in Yemen is also draining the kingdom's coffers, and the war will become more costly as it drags on.

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