I guess it's unconstitutional because it's not in the Bible. Or maybe because the president isn't really an American citizen, he's actually a space alien (and a Muslim one at that). There simply is no rational argument against a public option. All opponents have to go on is lies and scare tactics.
I'm glad the debate was civil, but it's hard to have a truly honest discussion without acknowledging who the senators are really working for. The five Democrats who voted against the public option all have received major campaign contributions from the insurance industry. In an otherwise silly article, the National Inquisition lists just how much each received. It's worth checking out. http://www.natinq.com