Say what you mean Senator McCain. Take away the rhetorical flourishes, and your letter to Senator Barack Obama, Democrat from Illinois, is so vague that it makes no sense.
You claim that Senator Obama gave you "private assurances" he had a "desire to cooperate in our efforts to negotiate bipartisan lobbying reform legislation." Senator McCain, a "desire" is not a promise. Any Democrat who wants to pass legislation in the Senate must cooperate and negotiate a bipartisan solution, since the Republicans have a clear majority. And "our efforts" are whose? You knew full well that Senator Obama was a co-sponsor of S.2180, the Honest Leadership and Open Government Act.: What were you expecting, that the Senator would switch his support toward your bill, S. 2128, the Lobbying Transparency and Accountability Act? You end by claiming, "in politics the public interest isn't always a priority for every one of us." Exactly how is S.2180 not in the public interest?
Finally, something makes no sense to me. You say Senator Obama used the "typical rhetorical gloss routinely used in politics to make self-interested partisan posturing appear more noble." Politicians do that in public all the time. But these were private assurances to you. In such a context, why would Senator Obama bother? What would he get out of it?
In all candor Senator McCain, your bitchy insinuations crowd out the substance of whatever message you wished to convey.