Who besides you said anything about Cheney? The post isn't about Cheney -- it's about the tone of the White House press secretary. Nobody expects the White House to agree with Cheney. The issue is whether, when differing with someone (especially a former VP), the White House should cheapen itself with comments like, "I guess Rush Limbaugh was busy so they trotted out the next most popular member of the Republican cabal."
The high road here would have been to say something like "Former Vice President Cheney is certainly entitled to his opinion, but given the situation the president doesn't agree."
Even in the most heated debates in Congress there's a tradition of decorum -- terms like "my esteemed colleague" or "the distinguished gentleman." America expects those in high elected office to conduct themselves with class and dignity out of respect for our democratic principles. Our president is sitting in the same position as Thomas Jefferson and Abraham Lincoln -- we don't want to see that legacy cheapened by acting like a spoiled child.