Mike...
F18 Worlds is set up based on berths that sailors have qualified for... the U.S. only gets a couple right now.
I think there is a chance to qualify for a berth on site... but still it wouldn't necessarily lead to a large U.S. only attendance
While yes, the US F18 population has only allotted us 6 or so slots in the past, the host country usually gets many more berths by default in the year they host the event.