Interesting comments about Saudi Arabia and terrorism. A lot of people believe the real causes of radicalisation can be traced to Wahhabism, the regressive type of Islam dominant in Saudi Arabia. Western governments have long known this, but rarely refer to it because they dont want to offend the Saudis. This has been the track record of the government since at least 9/11. They will look in any direction except Saudi Arabia when seeking the causes of terrorism.
Trying to understand why they are never held to account I believe has to do with our petrodollar status. The necessity to have dollars in order to purchase oil in the global market creates demand for the dollar. That is a BIG deal for our economy. The value of the dollar is directly tied to demand for the dollar. Supply and demand, basic economics. The petrodollar status is what holds up the value of the U.S. dollar. Looking at it from that point of view it's easy to understand why every American government, democrat or republican goes out of their way to placate them. And long as that is place I don't see anything changing far as the Saudis are concerned.