At the age of 78, why does Shimon Peres, a Nobel Peace Prize winner, want this job? The question looms larger as Israel’s response to Palestinian violence grows more aggressive. Peres hopes his partnership with Sharon can halt the steady slide toward war. “I feel myself responsible… to bring an end to blood, to fire, to hatred,” he told NEWSWEEK. Throughout his 50-year political career, Peres has been both a dreamy idealist and a cunning tactician. But now even some of his oldest allies think he’s the one who’s being used. Yossi Beilin, long the most dedicated of his political disciples, says Peres has become a “fig leaf” for the government’s worst policies in the West Bank and Gaza, tarnishing his legacy. “If Sharon decides to launch something big, he will use Peres to justify it,” Beilin says. “It is a stain that will be there forever. It is the mark of Cain.”

Despite sniping from his main power base, polls show Peres enjoying broader popularity these days than at any time in his career. With the intifada causing a sharp mood shift to the right, many centrist Israelis are happy to see Peres and Sharon sharing power. Ari Shavit, a prominent writer for the newspaper Haaretz, says Peres has not only moderated Sharon, he’s actually prevented war. “Now he’s earned his peace prize,” Shavit says. “In an ironic way, this is his finest hour.”

Other supporters hark back to a cabinet meeting in June, when Israel weighed its response to a bombing that killed 21 Israelis in Tel Aviv. A participant told NEWSWEEK Sharon was ready for drastic measures, including round-the-clock air- strikes on the West Bank and Gaza. After an impassioned plea by Peres, the cabinet decided on a more restrained response.

But as violence cascades, it will become harder for Peres to limit the scope of Israeli retaliations. “I don’t have a majority [in the cabinet], and I’m not a superman,” Peres said, “so my only chance is to reason.” That’s a dubious proposition in the Middle East, and it leaves the aging statesman in a perilous position. If Peres can’t prevent war, he may be a party to it.