In a stunning turnaround reminiscent of Harry Truman's 1948 election, Prime Minister Menachem Begin has converted Israel into a private stage all his own and the June 30 election into a one-man show with disquieting implications for the opposition Labor Party and the United States.

The exultant mood now surrounding Begin's extraordinary comeback broke through during an outdoor campaign speech May 27 at Rehobot. During a pause in his electrifying one-hour display of campaign rhetoric, a young Oriental Jew shouted: "Menanchem Begin, king of Israel." He has come to dominate the campaign so thoroughly, with both economic and foreign policy issues for the moment working powerfully in his behalf, that Shimon Peres, who leads the Labor opposition, is reduced to a single strategy: make Begin the only issue.

Attacking Begin in an indoor rally the following evening in the coastal town of Holon, Peres--no match for Begin as a stump speaker--moved one Labor partisan to shout: "You should not criticize the prime minister." Peres shot back: "Begin, Begin, Begin, who is he that he cannot be criticized? Is he a new Khomeini?" But in making Begin the central issue of the campaign, Peres risks building him up, unless events in the next four weeks hand him new ammunition.

In the last three months, including the still-touchy Lebanon crisis, the ammunition has been coming Begin's way, filling his campaign artillery with heavy explosives. With his politiclly brilliant handling of the unceasing economic crisis, Begin's finance minister has dipped into a bit of supply-side economics to put masses of new spending money into the pockets of hard-pressed consumers. He has brought such choice goods as color TV sets within consumer spending range and restored food and other subsidies for the low-income Sephardic and Oriental Jews who are Begin's solid constituency.

Perhaps more important, however, is the way Begin has either managed or lucked out of the Lebanon crisis. Begin's cautious refusal to use Israeil air power against Syrian missiles in Lebanon has reinforced his "peace and security" campaign slogan. His voice dripped with scorn in Rehobot when he recalled Labor's warning four years ago that if Begin became prime minister, he would take Israel into war the first day.

His voice dropping low, he asked: "Where is the war?"

He has Peres outflanked and in what looks like a political vise on Labor's continuing effort to convert him into an Israeli Attila.

Although Peres tries to ridicule him for withdrawing Jewish settlements from Egyptian Sinai, after saying "not one grain of sand" in the Sinai Desert would be returned to Egypt, he sounds hollow.

Peres and his Labor coalition enthusistically backed the Camp David accords. Moreover, neither Peres nor any other Labor leader is credible playing the game of hawks and doves against Begin.

While Begin struts his one-man campaign around Israel, the high command of Peres plots new ways to bring him down as a man not to be "trusted," as proclaimed in Labor's heavy newspaper advertisements. But events keep overtaking their best-laid plans.

A case in point is Begin's summit meetingwith Egyptian President Anwar Sadat scheduled for June 4 at Sharm el Sheik. That stunner, which clearly displays Begin as the winner in the eyes of the shrewd Sadat, outflanked Peres' own effort to arrange a meeting with Sadat, who suddenly has become a factor in Israel's national election. The obliging Sadat agreed quickly to meet Peres--but in Egypt, enaccessible to Israeli television sets.

Likewise, Peres' decision to seek a special session of the parliament to berate Begin for his secret promise to Christian Phalangists in Lebanon may well backfire. It never had prior approval from some of Peres' top running mates, including retired Gen. Haim Bar-Lev and former prime minister Yitzhak Rabin.

Begin is riding a fast-moving crest, despite his running battles with the United States, his serious 1977 heart attack and the "untrustworthy" cry of Labor. Clearly helping him, in addition to temporary improvements in the economy and his handling of the Lebanon missile crisis, is the new Israeli nationalism he has worked hard to infuse the past four years.

That new militancy, strong among the rising percentages of Sephardic nd Oriental Jews, enhances his chances of winning June 30. But it also portends deep problems for the United States if Begin's margin holds during the next four weeks, a subject for another column.