This op-ed page saw fit to carry last week a sour attack on David Harris, the executive director of the American Jewish Committee, who happens to be one of the Jewish world's finest public servants. I strongly feel that a bit of "bi'ur hametz" is necessary. I do not wish to enter the debate or dispute the accusation against Harris, who certainly does not need me as a defense attorney: His personal prestige and esteem is well established. What matters most is the wrong impression the readers may be left with as to the complexity and the critical role played by the AJC (and other Jewish organizations) in the service of Israel, the Jewish world and democracies in general. I am writing not as an angry friend of Harris's (I am not) but as a concerned scholar of the Diaspora, with years of research and intimate knowledge of the Jewish world behind me. The study of the role played by various Diaspora communities in world affairs is a growing field, to which I have made some contributions. The Jewish people and Jewish organizations, like the AJC, are often envied, admired and emulated by other diasporas and their countries of origin for effectively sustaining the links between Israel and the Diaspora communities. In my books I show how the Jewish Diaspora in general, and the AJC in particular, are in its links to Israel regarded by scholars as an model for what we call "a fully developed paradigm of diaspora-homeland relations." From my perspective, gained through years of academic study and first-hand observation, there are very few instances, if any, which equal the achievements of the AJC under David Harris's leadership as an effective tool of nongovernmental advocacy and international diplomacy in Europe, the US, the Caucasus and India, including the Indian diaspora in America. David Harris and his team are sophisticated, savvy, sober and incredibly successful Diaspora leaders and activists. In my own work I have come across the critical role played by the AJC, even before Harris's time, in interreligious dialogue, and especially in laying the foundations for the profound transformation of the Catholic Church toward the Jewish people and the State of Israel. The work of AJC's Rabbi David Rosen is particularly critical in the domain of interreligious dialogue in the past few years, not only with the Church but also in the Islamic world. These issues may not be considered critical by Israelis, but they are. In my work on German-Israeli-Jewish-American relations, I found that it was Harris's daring advocacy of strong, direct relations with Germany - not an easy path for any American Jews to take - which helped cement a commitment of utmost importance to the future of Israel and the trans-Atlantic relationship. Harris and other AJC lay leaders are respected in Germany and other parts of Europe, and their voice is important in the corridors of power in Berlin and Paris, among many other places. The transformed attitude of the new French president toward Israel - while clearly reflecting Nicolas Sarkozy's own identity and preferences - was "locked into place" by constant and discreet work in Paris, and by Harris's ability to offer Sarkozy a highly valued nongovernmental public platform in America. The AJC also took a stand on NATO expansion - its Rabbi Andrew Baker was instrumental on this issue - which gained for the Jewish people and, in effect, for Israel a loyal thanks from Eastern European countries where Jews have hardly been popular in the not-so-distant past. AJC offices in states of the former Soviet orbit worked hard and successfully to combat new signs of anti-Semitism. It would have been more emotionally satisfying to let loose verbally and tear into these new nations for their past sins, but looking toward the future, the AJC smartly turned potential foes into active friends. Much of AJC's most effective work is done behind closed doors. The fruit of such efforts in terms of the Jewish people and on issues which matter the most to Israel are garnered quietly. For those of us who observe Diaspora diplomacy on behalf of the Jews in Israel, it is clear that David Harris and his organization deserve great credit. The writer is head of the Abba Eban Program of Diplomacy at Tel Aviv University and the professor and founding director of the Center for Jewish Civilization at Georgetown University. His latest book is Kinship and Diasporas in International Affairs (Michigan University Press 2007).