Shimon Peres's announcement Wednesday that he is leaving the Labor Party signals the end of an era, even if he still returns as a minister in the new government, as he may if Ariel Sharon wins reelection. While Labor's historic tendency to engage in debilitating family feuds seems unchanged, the party itself clearly has shifted, and in a way that has left Peres sidelined. For better or worse, Labor is now genuinely refashioning itself as a social crusader, an identity it had effectively abandoned decades ago. Ironically, it was Peres, who as co-founder of the Rafi Party that seceded from Labor in 1965, coined the slogan "a car for every worker." Behind that stock populist line lurked an economic pragmatism that placed prosperity ahead of welfare. Two decades later Peres would turn that knowledge of the necessity of reform into reality. In abolishing - as prime minister at the time - subsidies for food and public transport, freezing public sector pay, slashing wage indexations, axing public sector budgets, lifting import duties and empowering the Bank of Israel to set interest rates independently, Peres effectively halted the public sector's growth, disempowered the Histadrut, and jump-started the long process whereby ours became a mature, predominantly free market economy. Peres did to orthodox socialism pretty much what Ariel Sharon would later do to unreconstructed proponents of the "Greater Israel" approach. He therefore sought a new flag behind which to rally both Labor and the public. His choice, the peace cause, was wise, and his tool, an agreement with King Hussein that would have restored much of Amman's responsibility to the West Bank, was visionary. Considering the outbreak of the Palestinian uprising in fall 1987, several months after the deal with Jordan was shelved by then prime minister Yitzhak Shamir, Peres's London Agreement might have averted much of the last 18 years' Palestinian-Israeli violence. However, the violence did erupt, Jordan left the scene, and Peres - now as Rabin's foreign minister - made the fateful mistake of placing his, and the nation's, bets with Yasser Arafat. Later, as Palestinian terror raged and Peres joined Sharon in besieging Arafat, building the security barrier and killing terrorists, a new centrism seemed to emerge between them. Peres's colleagues in the Labor Party, however, have a different agenda, one that is dominated by a desire to restore Labor's distinctiveness in general, and focus on social issues in particular. That is how Labor ended up, in spite of Peres, consigning foreign affairs to the back burner, and opting for the kind of socialism that he was instrumental in undoing. In this regard, Peres, in addition to the usual personal rivalries, parted ideological ways from the party with which he has been synonymous for decades. Yet Peres's departure from Labor is significant not only ideologically. The vice premier's elaborate political career began not as a lawmaker, but as a technocrat, a powerful executive who as Defense Ministry director-general created an aerospace industry from scratch, masterminded an alliance with France and conceived Israel's nuclear program. These and other accomplishments promise Peres a place of honor in the history of the Jewish state, but they also made of him a public figure even when he had no need to interact with the public. By the time he joined the Knesset, in 1958, Peres was already so intimately familiar with the political, military and financial elites that his career seemed to not need the daily hobnobbing that is a prerequisite to most political ascents. When he began dedicating his time to interacting with the public, as an aspiring prime minister, Peres was already in his fifties, and only then did it emerge that he was incapable of stirring the masses. When Peres first joined Sharon in the government, he was considered the ultimate stamp of international legitimacy on a leader who was then still in transition, in the public's eye, from the political wilderness to representing the Israeli mainstream. Now Peres has become a mixed blessing for Sharon, attracting some and repelling others, but in any case more of an accoutrement than a potentially critical asset. It is thus in two senses that the Peres era has ended - both in terms of his looming over Labor, and in terms of the replacement of his insistently diplomatic approach with Sharon's new, thus far unilateralist, paradigm.