While it is no way takes away from the suggested solutions to the problem, it is worth noting that the problem of decreasing membership is a worldwide issue and not unique to the US. Take a look at John Roake's summary of worldwide membership statistics. You will see that the decline is everywhere including in those European countries we often seek to emulate. Note also that the production of world champions (something the original post highlights as a concern) does not in any way correlate to membership stats. Poland, for example, has had one of the steepest declines in membership over the last decade yet in that time has risen to be the the top in contests.
http://www.lkka.cz/sport/zapisy/Zapi...03.30_2.P2.pdf
So, the question is not what is being done wrong in the US (or my country, Canada) in particular, but rather what can change within the worldwide soaring community? We can look to best practices from abroad yes, but there may very well be things we do that those abroad may want to consider as well.
We also have to consider what the end goal is. Soaring is both a sport and an activity. Success can be measured by bums in seats or by seats on podiums. and as the Poles have shown us, the two are not necessarily one and the same.