The long, agonizing centerpiece to Kippur, Israeli director Amos Gitai's semi-autobiographical film about the 1973 Yom Kippur War, shows a group of soldiers slogging haplessly through the mud without making any progress, each step driving them deeper into the muck. The anti-war metaphor can't be missed, but the scene is also emblematic of the arid, joyless rigor that suffuses Gitai's work, which evokes displacement and oppression with barely a glint of hope. His wide-ranging concern for Israel's social and historical fabric, to say nothing of his prolific output of fiction and documentary features, has made him a formidable presence on the international scene, but his films are often easier to admire than actually watch. As if to assert himself as the least sensual of major filmmakers, Gitai's grueling Kedma opens with a painfully desultory sex scene aboard the title vessel, an old cargo ship transporting war-weary Jews to their new homeland in May 1948, just days before the State of Israel becomes official. In a masterful sequence–the first and last in the film–Gitai opens with seemingly intimate close-ups of the couple, then pulls back to reveal a catacomb of adjoining bunks and onlookers crammed into a tight space. Having survived the Holocaust, they approach the Palestinian shore with an anxious silence that Gitai captures with palpable tension, knowing that they're about to escape from one tragic situation to another. Once their unauthorized ship reaches its destination, the refugees are greeted with British gunfire intended to drive them back, but most are able to flee with the help of a Jewish underground force that tries to lead them into the Holy Land. The sketchy characters, defined by one monologue each, represent a bouillabaisse of ethnicity and runaway accents, including a Russian woman who spent years in a Siberian prison, a young cantor who lost his parents and his faith in the war, an angry Palestinian farmer, and a self-hating Pole worn down by suffering. Never one to back away from provocative areas, Gitai views the events like a crystal ball for the next 50 years and beyond, showing a nation born amid chaos and tragedy, with Arabs and Jews thrown into an endless cycle of persecution and exile. But Kedma's success as a conversation piece is tied to its failure as a drama, due to Gitai's irritating tendency to give his characters ironic deaths or use them as sounding boards for his "prescient" observations. (Palestinian farmer: "We'll father generations of rebellious children!") Gitai convincingly pinpoints a key spark in an ongoing conflict, but Kedma makes for a clumsy, lugubrious history lesson.