you are correct kind sir the USGA and no one eles controls the course layout, the starting times, the sun rise and sun set of the us open, if you want to play in it, you have to qualify according to USGA rules. you dont need to be a member of any pga, euro or asian tour. Anyone can qualify, however, you will be competing agaqinst many PGA tour pros to get a spot. First step is to fill out an application, then if you are accepted, you will be given a Tee time at one of the USGA sponsered places somewhere in the US. It is harder to qualify for the US open than it is to get to the moon in a hot air balloon. But you could do it... but i recomend that you don't try if you have over a 2 handicap.