Jack:
I was going to mention Butler, but didn't, assuming the club won't budge on its membership policy. They almost certainly would've hosted a U.S. Open by now, given the USGA's desire to tap into the Chicago market, so my sense is that it will take a substantial change in the membership's view on things to host an Open there. By all reports, it's a worthy candidate on golf architecture/infrastructure merits alone.
John Kavanaugh -- There is an interesting back-story to Whistling Straits (a Dye course) not hosting a U.S. Open that it was angling for, right about this time. Several years ago, WStraits founder Herb Kohler was really pining for the U.S. Open at WS, but -- having hosted the PGA at the course -- also had good connections there with the PGA higher-ups. When the PGA offered him two PGA championships (2010 and 2015) and the Ryder Cup (2020), Herb said it was simply an offer he couldn't refuse. That set back his plans to host the U.S. Open at WS, and the development of Erin Hills has further complicated the matter. If Davis and the USGA view EHills in 2017 as anything remotely close to being successful, I think you'll see the U.S. Open back there (perhaps multiple times) before it ever goes to WStraits.