In this thesis, I investigate the influence of the pro-Israel lobby, as a means of assessing more generally the role of interest groups in shaping American public policy, and whether the so-called “lobbies that can’t be beat” are truly unassailable. First, I probe the prevailing treatise on pro-Israel lobby influence, which portrays the American Israel Public Affairs Committee (AIPAC) as the nerve center of a pro-Israel lobbying network that almost never fails to coerce policymakers to bow to its will. I ask two distinct but related questions: do AIPAC and the other groups depicted as the “Israel lobby” wield as much power as the authors’ claim, and how accurately do they illustrate the means and mechanisms through which such influence is exercised? Second, I present a case study of a pro-Israel organization, J Street, at cross-purposes with the centrist pro-Israel lobby whose founding and expansion challenge the perception of pro-Israel lobby cohesion and dominance that pervades the existing literature. In the first chapter, I summarize John Mearsheimer and Stephen Walt’s The Israel Lobby and U.S. Foreign Policy and conduct a comprehensive review of the literature surrounding the controversy aroused by the book. I present the foremost academic, media, and other responses elicited by the treatise to distill a ‘conventional wisdom’ on the pro-Israel lobby. While I find the perception of pervasive pro-Israel lobby influence in policymaking and public discourse is largely accurate, I nonetheless conclude the book’s empirical claims on pro-Israel lobby influence are exaggerated and bordering on fallacious. Further, I conclude the book’s claims regarding how lobby influence is gained and exercised and the extent to which such influence operates are, in light of the paucity of systematic empirical evidence provided in the book, imprecise. In the following chapter, I present a preliminary case study of J Street, a dovish pro-Israel lobbying organization which rose to prominence after Mearsheimer and Walt’s treatise was published. I detail how J Street came to be and how it has already begun to made its mark on the American Jewish community, established pro-Israel lobbying groups, and U.S. policy toward Israel, tracing the organization’s successes and struggles through its first four years of existence. I find that Mearsheimer and Walt, and their panoply of critics, minimize the profound changes taking place in the Jewish community regarding Jewish communal affiliation and attachment to Israel; they also underestimate changes in American society generally regarding American relations with Israel and the perception of the deleterious influence of the pro-Israel lobby on policymaking and public discourse. It is this disregard that prevented Mearsheimer and Walt and their various critics from anticipating the advent of J Street. Though still a fledgling organization, J Street has begun to transform the pro-Israel landscape by broadening the tent of acceptable pro-Israel discourse within the Jewish community, and by becoming an increasingly well-heard, if not always heeded, lobbying presence on Capitol Hill. J Street’s founding and organizational expansion renders Mearsheimer and Walt thesis increasingly void, above and beyond the faults exposed by its multitude of critics. This thesis is intended to contribute to the larger literature on interest-group politics by demonstrating that the “pro-Israel lobby” is neither monolithic nor invincible. The pro-Israel lobby, led for decades by AIPAC and other centrist groups, did not win every legislative battle, and has had to accept major compromises to maintain its significant influence. No more than the NRA, AARP, or U.S. Chamber of Commerce--in their respective spheres of policy influence--is the pro-Israel lobby a lobby that can’t be beat, or an influence network that prospers without effecting compromises and bargains. My main point is that AIPAC and the rest of the centrist pro-Israel lobby are not the whole story. The influence of the pro-Israel lobby cannot be adequately understood without taking into account the increasingly weighty role and countervailing political influence of the other pro-Israel lobby in the policy subsystem that crafts U.S. policy toward Israel. While this thesis is hardly a definitive exposition of pro-Israel lobby influence on American life, I argue that the analyses, arguments, and findings proffered present a compelling counterpoint to The Israel Lobby.