Mark Twain is supposed to have said, “Never pick a fight with someone who buys ink by the barrel.”

After Paul Krugman made some relatively mild, and completely accurate criticisms of Obama’s health plan, the Obama campaign decided to go with some remarkably bogus oppo research where they selectively quoted, and misquoted Krugman.

Stupid move, but typical of a candidate who has never had a serious electoral challenge from a Democrat.

So, now the most popular, and most widely read liberal commentator in the United States has decided to go further, and criticise the most basic theory of Barack Obama’s campaign, his call for an “end to partisanship”.

It’s no one’s fault but Obama’s. He took a mild difference in policy, and

This shows just how unprepared Obama is for the big time.

Mr. Edwards replied, “Some people argue that we’re going to sit at a table with these people and they’re going to voluntarily give their power away. I think it is a complete fantasy; it will never happen.”

This was pretty clearly a swipe at Mr. Obama, who has repeatedly said that health reform should be negotiated at a “big table” that would include insurance companies and drug companies.

On Saturday Mr. Obama responded, this time criticizing Mr. Edwards by name. He declared that “We want to reduce the power of drug companies and insurance companies and so forth, but the notion that they will have no say-so at all in anything is just not realistic.”

Hmm. Do Obama supporters who celebrate his hoped-for ability to bring us together realize that “us” includes the insurance and drug lobbies?

It gets better. Go read it.