Ezra Klein suggests that 'the path of wisdom' would be for Obama to 'set precedent' for the campaign, saying something like:
Look, you want to ask me about his plan for a 100-years in Iraq or more tax cuts for the rich or better deals for telecom lobbyists, we can talk about that. But his personal life is not only none of my business but, frankly, it's none of yours
Klein is right, though most respondents on his blog seem to disagree. Those charging Klein with naivety - saying that 'being nice to the Republicans doesn't make then nice to you' are missing the strategic point, which goes beyond the innoculation/self-protection of Obama further down the road.
This is an opportunity for Obama to do the right thing. (Any political advantage arises primarily from being seen to do the right thing, even if there might seem to be short-term political gain in not doing so).
But there is a political advantage here too. Obama would get to define and project what breaking with the 'same old politics' means for him. And an early counter-inuitive move could help to frame his candidacy and the race for those voters who wait for a General Election race to shape up before paying too much attention.
As that would become an argument about how he believes the General Election should be fought - and here he gets to set a challenge for McCain.
Obama would have to fight the General Election saying: there is a deep clash of different visions for America, of different policies and politics, but I respect my opponent and do not need to question his integrity to disagree fundamentally about these issues. (Hence Obama's saying in his victory speech on Tuesday night:
"I revere and honor John McCain's service to this country. He is a genuine American hero. But when he embraces George Bush's failed economic policies, when he says that he is willing to send our troops into another 100 years of war in Iraq, then he represents the policies of yesterday. And we want to be the party of tomorrow. And I'm looking forward to having that debate with John McCain."
Those arguing that 'this is war, if we fight nice and they fight dirty, we lose' miss the point. That simply is not an option for Obama: it would be inauthentic given his core campaign message.
Obama then gets to challenge McCain to respond in kind.
If McCain does so, Obama has the tone and framing for the type of General Election he wants.
If McCain does not do so, then it is he that has the authenticity problem. What happened to 'straight talk' John McCain? Having been the victim of a Bush/Rove personal destruction campaign in 2000, is he now using or (more plausibly) passively benefitting from such tactics himself?
If Obama had publicly defended McCain, it would raise the bar for McCain to distance himself from attempts to Swift Boat Obama by Republican surrogates. Yet there is a political trap here too. McCain's distancing himself from such attacks could raise questions from the sceptical base about how much McCain wants to fight and win as a Republican. (And liberals doing the right thing by McCain now could help here too).
(Obama would also get to draw an implicit contrast with the Clintons. That is mostly in his favour, though would confirm the doubts of those who fear Obama will be chewed up and spat out by the Republican attack machine).
Ultimately, if Obama is offering a different kind of politics, he needs to use potentially defining moments to act consistently with that.
This has been the primary season when going negative backfired. And so Obama versus McCain could be the type of General Election that much of the United States wants and needs. (There is plenty there for partisans too: please, please, please don't give me the usual nonsense that you can't find any real differences between these two candidates).
Just not for those who believe that democratic elections should be all-out partisan war, with no holds barred. After all, both of these candidates would know that one of the lessons of the Bush era is that rules of conduct matter, even at war.
* UPDATE: The New York Times' own public editor Clark Hoyt argues against publication in his column.