Miller is actually not entirely right. The Hummer line was built to capitalize on the fame of the H-1 and the market for the biggest, baddest SUV. While off-road capability was part of that, The rest was status and exclusivity. The idea being is that what was selling. Why sell a Tahoe when you could sell very basically the same truck, for a larger profit margin. If GM was trying to compete with Jeep they would have built much smaller vehicles. While the H-3 was a shot at that part of the market, it was poorly conceived and executed. Had they actually produced the original concept, (short bed regular cab) I believe it would have taken off with a much better following in that market. Instead they turned it into a TrailBlazer, which was not the greatest seller anyway.
As a big fan of the H-1, and GM, I was extremely disappointed in all of the Civilian Hummers. They started out as a very capable but big military vehicle. It was this because of it's sparse interior, and some loss of comfort and "luxury" in exchange for off road capability and utility. In the translation into the H-2 and H-3 line they forgot what made the H-1 so successful. They took utility and ability out in exchange for luxury and status, and therefore killed the line. Now they could not keep up with a jeep on the trail, and the luxury was found in both the Caddy and Tahoe, without the looks of the Hummer. (never a strong point)