Although US President Donald Trump presents “real opportunities,” his “unpredictability is a double-edged sword,” famed lawyer Alan Dershowitz told The Jerusalem Post Conference in New York on Sunday.On the positive side, Dershowitz argued that “there are real opportunities with this new administration to do something constructive in the Middle East. When the US has Israel’s back and Israel feels strong, it is willing to make compromises and concessions.”On the negative side, he said, “President Trump is utterly unpredictable. We don’t know what he will do next. We don’t know what surprises” are next, and “we didn’t know what he would do with” Palestinian Authority President Mahmoud Abbas.“Unpredictability is a double- edged sword. It could drive people together, but it also produces uncertainty, so it could make it more difficult to come to a resolution,” Dershowitz said.Overall, he suggested that Trump’s real Middle East policies will become more clear in the near future as he visits in the region in late May.Another major message Dershowitz had was a surprisingly strong condemnation of various groups on the American political Left, despite his affiliation as a lifelong Democrat.He said US “progressives have abandoned” Israel, and that such “progressives are repressive... want to bar pro-Israel speakers and... are intolerant.”Further, he called on American Jews to “marginalize progressives within the mainstream Democratic party,” saying that he will fight bigotry on both the American political Left and Right.The renowned lawyer also advocated maintaining Israel as a bipartisan issue in the US, and it appeared his anger was directed at groups on the Right and Left that he believes are trying to break up the bipartisan stance on Israel.Dershowitz also said Jews of different political orientations and beliefs need to focus on “the 80%-case” issues, such as valuing Israel as the state of the Jewish people, that it has a right to defend itself, and that antisemitism must be carefully watched. He characterized groups like the Zionist Organization of America and J Street as representing only 20% of Jews, on the far ends of the spectrum, and that such groups and their ideologies should not be the general community’s focus.