I'd like to rebut the message from BillMC. I am VP of the Seattle IPMS Club - 126 members strong. When we tried to host the Nationals (for 2016), the IPMS National office was not the problem at all. They were very helpful, answering all of our questions regarding securing the venue, contacting vendors, visitor metrics - everything. They also take all the financial risk.
We have five clubs in the area who were willing to band together to run the show itself. We successfully secured the venue and the hotel, and had figured out the food, rooms and tours - we were on our way to hosting the 2016 event. We simply fell short of the key people we needed to manage the project. We needed about eight, we had 5. These critical 2-3 year-out jobs are not something you can convince someone to do - they have to really want to do it. And we fell short (this time). As a group, the membership voted to pull out.
So - lack of long-range volunteers were to blame. To attribute any of this to the National office of IPMS is simply wrong.