They lost the argument because they took it personal and made it personal, and counted on conservatives to back them instead of the president.
It absolutely undermines Bush and we all know it thanks to technology. In most workplaces, offices, sports fields, call-in radio, no one is talking about Miers.
People just don't care because she isn't threatening or frightening to their wellbeing. The critics don't seem to get that at all.
Bush is responsible for undermining Bush - not those that are puzzled by his bizarre behavior.