Peter Parks/Agence France-Presse-Getty Images, top Compared with the average Gulfstream jet, a Hummer H2 can seem downright fuel efficient. THERE are objects or possessions that scream "I'm better than you" - items that remind the average Joe of a cultural and economic divide that cannot be crossed. It's a $10,000 bottle of wine, a Hummer, a real Rolex. This year's conspicuous object seems to be the private jet. Once, this prized possession was associated with corporate executives and reclusive stars. Or with congressmen on a junket. There was nothing political, or at least nothing partisan, about them. But since...