When Professor Alan Dershowitz spoke to hundreds of pro-Israel supporters at the University of Pennsylvania last week, many understood him to be simply providing a broad-strokes counter-message to the anti-Israel Penn BDS (boycotts of, divestment from and sanctions against Israel) conference which began the next day on the same campus.

But while Dershowitz was there in the ostensible role of "lover of Israel because I am a liberal Democrat," a close listening and gentle unpacking of many of his standard lines reveal more nuanced positions relating to Israel than many typically understand him to espouse.  The nuances are very important, especially because they come from so committed a tribunal of the liberal left.

Indeed, while the left believes Dershowitz to be reflexively and unquestioningly pro-Israel, the right frequently sees him as reflexively pro-Obama Democrat and rigidly anti-"settlements."  But within minutes of the start of a short press conference preceding the official events at Penn, Dershowitz angrily denounced Media Matters, an entity closely aligned -- and, in his view, that alignment may prove fatal to the election -- with the Democratic party, and firmly rejected a straight-line "the settlements are the problem" position.

Max Blumenthal, an attention-seeking, self-described "Cultural Marxist," is the son of former Clinton speechwriter Sidney Blumenthal.  Despite having access to the rich and powerful through his family connections, Blumenthal, still an adolescent though now in his mid-30s, revels in acting out in public and throwing spitballs at "the establishment," most especially the hated "neo-cons"...or, really, anyone who believes that Israel is an important ally of the United States.

Blumenthal was a participant in the recent Penn BDS conference.  On the day of Dershowitz's talk, Blumenthal penned a column for the Daily Pennsylvanian, the university newspaper, shamefully titled "Torture, Violence Advocate to Keynote anti-BDS Event," with the sub-heading: "Alan Dershowitz, supporter of bulldozing Palestinian towns and torturing criminal suspects, is coming to campus."

When asked about Blumenthal's DP article, Dershowitz looked exasperated and listed all the ways in which that article got everything wrong.  For example, Dershowitz is opposed to torture.  Dershowitz has called for something called "torture warrants" to ensure that extreme measures be applied only in extraordinary circumstances and with the most extraordinary of safeguards.  Blumenthal's  distorted analysis?  Dershowitz supports torture. 

Much more newsworthy than the silly spitballs Blumenthal threw with his screaming article was Dershowitz's conviction that Blumenthal and his buddies at Media Matters (a media watchdog organization affiliated with the Democratic party and which has recently been widely accused of engaging in anti-Semitism) were going to cost this president the election.

Asked at the pre-event press conference whether he had seen Blumenthal's article, Dershowitz's immediate and angry response was: "I have, and let me tell you, Max Blumenthal and Media Matters will be singlehandedly responsible for [Obama] losing this election.  They [the Democrats] cannot win the election and keep this affiliation with them [Media Matters]."

When shown this statement, all Blumenthal could muster (via Twitter) was that "I haven't been at mmfa [Media Matters] since 2007."  It was pointed out that Blumenthal's then-current Facebook page listed him as working for the "progressive organization Media Matters for America."  Blumenthal did not respond, but he has since altered his Facebook page so that only those "lucky" enough to be his FB friends can see it (although you can still look at the dozens of pictures he posts of himself there).

In an effort to determine the firmness of Dershowitz's position against BDS, he was asked whether, if the Penn BDS conference only targeted its calls against the territories [of Judea and Samaria] would he still be opposed. "Absolutely," he responded.  "If they are interested in human rights, when what is the excuse for not applying BDS to China for occupying Tibet, and Russia, for its occupation of Chechnya, or  to Hamas or Hezbollah for their brutality and murders of civilians."   He explained, "The BDS of Israel, any part of Israel," is merely a pretext for hatred."  In other words, "partial" or "good" boycotts against Israel don't pass muster with Dershowitz.

When the topic of unfairness to Israel is under discussion, the issue of the United Nations invariably crops up.  The Philadelphia evening with Dershowitz was no different, but many of those who came to hear him that night learned something they had not known.

In the spring of 2010, Israeli Prime Minister Benjamin Netanyahu asked Dershowitz to become an Israeli citizen so that he could be appointed Israel's ambassador to the U.N.  "It would have been a crowning achievement to my life's work," Dershowitz explained.   He said he would have loved "the chance to kick some rear-end in that house of hypocrisy," sending the audience into peals of laughter and applause.  But he ultimately declined Netanyahu's offer because, while "being the Israeli Ambassador to the UN would have been great for me, it ultimately would have been bad for Israel and bad for the United States."

He explained that if an issue arose that forced him to choose between what was good for Israel and what was good for the United States, "it would have sent to a fevered pitch the 'dual loyalty' argument against American Jews." 

And so Alan Dershowitz remains somewhat on the sidelines -- a pro-Israel American whose case for Israel is appreciated by most, but often misunderstood by those at both ends of the spectrum.  In fact, Dershowitz frequently calls his take the "80 percent case" for Israel, and that's okay with him.

Lori Lowenthal Marcus is president of Z STREET and executive committee chair of the National Conference on Jewish Affairs.