Now this is fun.

An outraged Sen. John McCain (R-AZ) today called Sen. Barack Obama (D-IL) insincere and partisan, suggesting the Illinois freshman as much as lied in private dicussions the two had about ethics reform last week.

Obama sent McCain a letter asking him to cosponsor the Democratic proposal on ethics reform rather than appointing a task force on the issue.  McCain's response is one of the single most bitter, nasty letters I have ever seen from any Senator.  It's rather remarkable, actually, and gives the lie to the notion that McCain is of a bipartisan mind.

I'm having trouble opening the PDF of McCain's letter, so I'll take the text from Marc Ambinder and Patrick Ottenhoff's well-written blog post.

"When you approached me and insisted that despite your leadership's preference to use the issue to gain a political advantage in the 2006 elections, you were personally committed to achieving a result that would reflect credit on the entire Senate and offer the country a better example of political leadership, I concluded your professed concern for the institution and the public interest was genuine and admirable. Thank you for disabusing me of such notions with your letter. ... I'm embarrassed to admit that after all these years in politics I failed to interept your previous assurances as typical rhetorical gloss routinely used in political to make self-interested partisan posturing appear more noble. Again, sorry for the confusion, but please be assured I won't make the same mistake again."

Obama's spokesman, Robert Gibbs, called McCain's letter "confusing" and "headscratching." He said Obama "remains committed" to reform and will work with "any Republican and Democrat" who is serious about the issue. His letter to McCain, said Gibbs, signaled his preference "to get legislation through committee, rather than wait for a task force."

In his letter, McCain says that his task force proposal would ensure that meaningless or cosmetic reforms aren't rushed into law -- and that the solution in the end would reflect the interests of both parties and their voters.

His last line suggests that Obama will not soon regain McCain's favor.

Writes McCain, "I understand how important the opportunity to lead your party's effort to exploit this issue must seem to a freshman Senator, and I hold no hard feelings over your earlier disingenuousness. Again, I have been around long enough to appreciate that in politics the public interest isn't always a priority for every one of us. Good luck to you, Senator."

Bipartisanship is dead.  That's just true.  It's sad, but Republicans have become too partisan to work for the good of the country.  Voters will need to repair this at the ballot box in November.