In a blog post, Paul Krugman wrote about a unifying theory of what leads to broad spectrum of ideologies on both the right and the left. The theory he adopts is that the position one takes on any issue is generally determined by one's position on relating to traditional social hierarchies. If one believes in challenging traditional social hierarchies, that would lead to one set of policy positions, and a set of opposite positions would result from a belief in supporting traditional social hierarchies.
The examples Krugman offers are social insurance and social policy (gay marriage and the like). However, in principle, this could also apply to the Middle East. However, applying this principle to the Middle East would require first identifying what is meant by "traditional social hierarchy."
For much of the Left, there is only one "traditional social hierarchy" that matters in international relations, and that is of Europe dominating everyone else. Thus, if one views international relations through the lens of whether or not to support European world domination, a supporter would side with Israel while a challenger would side with the Palestinians. Hence, we see that much of the Right, which tends to support traditional hierarchies, sides with Israel while much of the Left, which challenges traditional hierarchies, sides with the Palestinians.
However, there are other traditional social hierarchies in play in international affairs. Within the Middle East, there is the region's internal traditional social hierarchy which placed believers at the top, Jews on the bottom, and Christians occupying a station any place in between. Viewing international relations through this lens, supporters of the Middle East's traditional hierarchy would side with the Palestinians while challengers of that hierarchy would side with Israel. Thus we see that right-wing racists like David Duke support the Palestinians while left-wingers with a perspective on Middle Eastern history like Paul Berman support Israel.
A further observation is that it is very difficult to oppose both traditional social hierarchies. Nearly any action taken to challenge Eurocentric hierarchy would have the effect of buttressing, in actuality if not by intent, the Middle East-centric hierarchy. This provides an explanations for an observation Elder of Ziyon made some time ago that leftist Israel-haters take great pains to emphasize that they have nothing against Jews while rightist Israel-haters are open about their Jew hatred. Support of the Middle East-centric hierarchy is inherently judeophobic. From the Left, hatred of Israel is not motivated supporting that hierarchy, even if their actions inevitably lend it a boost. In fact, anti-racism gets to the heart of their identity. Thus, they circle the wagons to defend their anti-racist self-image by asserting that their motives have nothing to do with the support to the Middle East-centric hierarchy that they invariably provide. In contrast, the right-wing supporters of the Middle East-centric hierarchy have no problem with the judeophobia that that hierarchy entails and thus have no need for the mental gymnastics to deny it.
Another example of which traditional hierarchy to select as one's lens comes from Peter Beinart. When he was promoting Crisis of Zionism, he said at interviews that the Zionist establishment was lecturing the younger generation that they should sacrifice liberalism on the altar of Zionism and discovered that their children had instead sacrificed Zionism on the altar of liberalism. This statement only makes sense through the lens of the Eurocentric hierarchy. The typical response to Beinart has been to emphasize everything that has happened in European Jewish history or the contributions that Israel has made to the world. For the likes of Beinart, this can all be summarized as saying that there should be an exception where the Eurocentric hierarchy should be tolerated.
However, we do not need to imprison ourselves in this lens. Viewed through the lens of the Middle East-centric hierarchy, there is nothing incompatible between Zionism and liberalism. However, view world affairs through this lens requires a greater scope of history than is required for the Eurocentric hierarchy. Thus, we need to teach history sufficiently to identify the pillars of the Middle East-centric hierarchy.
The Middle East is not the only region where the Eurocentric hierarchy is opposite the local-centric hierarchy. Indeed, in any non-western locale with an illiberal social hierarchy, challenging that hierarchy would be imposing Western values and thus establishing the Eurocentric hierarchy. Hence Ayaan Hirsi Ali who was a clear victim of the social hierarchy of her native Somalia is vilified by the Left because her escape from that culture exemplifies the triumph of European values of those of her native Somalia. Similarly, today's young Britons today question the authority of their country to outlaw sati in India on the grounds that they should not impose their values on other cultures.