Er, no. America existed a long time before the Saudi's came into the picture. Oil only became a key strategic resource about 100 years ago at which point the major powers started a scramble to control areas that had large amounts of it (middle east being the big prize). The house of Saud starting from 1902 conquered much of the Arabian peninsula consolidating power by the 1930's. In 1937 American surveyors discovered the oil and America allied itself to the Saud's in 1945 formally. Since then the family has accumulated over 1 trillion dollars in wealth and is one of the richest families in the world. Note that all this wealth originated from oil sales pretty much and a lot of their influence and wealth is used to keep them in power.
They have a formidable and loyal military, and have regularly butchered their own citizens if they dare ask for democracy. This is against pretty much everything the US stands for but US silence in criticizing them or sanctioning their oil to make them lose power pretty much is what keeps them in power. There is also anecdotal evidence that the CIA and other covert branches of the US government have actively assisted the Saud's stay in power. So yes, like I said, very hypocritical. Not the first time in US history and certainly not the last. I'd recommend listening to Dan Carlin's "American Peril" podcast to get a good understanding of the internal conflict America sometimes faces.
The issue with the USA is they have a constitution that is all roses and unicorns and they back that view for the world. Thing is when real economic realities bite (like the fact that economies run on oil) the US sometimes has to act against their conscience for their people's best interest. Hence they keep making these moves. Their occupation of the Philippines, their support of Saudi despotism, and a few other examples show how it plays out. Funny how those stories never make it into Hollywood movies. Its the shameful underbelly or real politik USA style.
The USA will find its conscience about the Saudi's the second the oil era ends, which it will soon. Mankind is always graduating up the energy scale. Started with wood, became coal, then oil, and the next step will be directly from the sun. Once the US economy is no longer reliant on external oil Saudi will suddenly become very inconvenient and lose its support from the USA and at that point I am guessing it will become another war torn middle eastern country descending into poverty and torn by civil war. The historical forces in play seem to point to that being the only way out.