Were the events of 1975–77 in Lebanon, commonly thought of today as an internecine sectarian war between Christians and Muslims, more comparable to the furies of revolution and counterrevolution? This article reframes the Lebanese National Movement's (LNM) “Transitional Program” as a revolutionary, anti-colonial, and radical republican challenge that sought to implement a new constitutional order based on popular sovereignty. Internally, it severed the link between sectarian affiliation and political representation that was the hallmark of the Lebanese regime. Externally, the program announced a commitment to popular struggle against imperially sustained settler colonialism in Palestine while calling into question the authoritarian practices of most regional regimes. Drawing from periodicals, memoirs, diplomatic sources, and interviews, this article considers the efforts of the LNM-PLO alliance to push the Transitional Program in the political sphere and on the battlefield. In turn, it demonstrates how the United States, Syria, Israel, and Lebanese counterrevolutionaries worked in concert to ensure that the sectarian regime would be preserved at the moment of its greatest challenge. Against a historiography that either dismisses the venture as predestined to fail or considers the period only within the shackles of post-defeat melancholia, it reevaluates the history of one of the most explicit emancipatory challenges to the Arab order.