The Saudis have trouble with a capital T and that rhymes with C and that stands for civil war — the one in Yemen, that is:
The Shia takeover of the government has caused Yemeni border security to collapse. Most of the border guards have left their posts leaving the Saudis to deal with a lot more smugglers and illegal migrants. This is a major problem because the border is 1,700 kilometers long and most of it is with Saudi Arabia. Yemeni smugglers make a lot of money getting people across and then transporting them north to where the oil and jobs are. Many migrants, who can afford it, keep going to Europe. In a normal year (when the bribable Yemeni border guards are on duty) the Saudi border troops catch and turn back over a million illegal migrants, but several hundred thousand are believed to get through, at least based on the number later found to have settled in the north or made their way to Europe where they were interrogated by police there. The big problem here is that some of those getting through are Islamic terrorists and that’s why the Saudis also stop those trying to cross illegally into Yemen. But with the Shia rebel success in Yemen the Saudis are now concerned with Iran-backed Shia terrorists and spies coming north. The Saudis could invade Yemen to deal with the problem but even the Sunni majority down there is divided, and not all factions are agreeable to a Saudi intervention. It is a very unpleasant situation for the Saudis.
With ISIL in the north and chaos in the south, it must be getting harder and harder for the Saudis to buy themselves out of trouble. While my heart doesn’t exactly break for them, my head tells me the House of Saud is still better than any likely replacement.