Gordon Brown today becomes the first British prime minister to address the Knesset, an honor not even extended to Margaret Thatcher, who in 1986 became the first British head of government to visit the Jewish state. We welcome Prime Minister Brown and trust that his message to Israel's parliament will be worthy of the historic occasion it marks. There have been other addresses to the Knesset's plenum by leaders of prominent EU states, including Germany and France, in connection with Israel's 60th anniversary. Brown, however, represents the nation whose historic role as the Mandatory power in Palestine played a large part in fomenting many of the crises that continue to haunt the Jewish state and its Arab neighbors. When Brown steps up to the Knesset podium, what ought to be uppermost in the collective British memory is that Britain was the power which, on the eve of the Holocaust, published its White Paper denying haven to desperate Jewish refugees from Hitler's Europe. The gates of Palestine closed. The gates of hell stayed open. BY A TWIST of fate, Brown is visiting the region just as a would-be annihilator threatens the state which the Jewish remnant built. The vitriolic rhetoric of Iran's Mahmoud Ahmadinejad and the nuclear weapons his nation seeks to manufacture are potentially as threatening as the Third Reich's Final Solution. Britain should feel a special responsibility to not - again - turn a blind eye to genocidal intentions. As Ron Prosor, Israel's ambassador to the Court of St. James's, has said: Britain ought "to take a leading role" in generating an effective global response to Iran's undisguised ambitions. The clock is ticking for the world, while its leaders appear content to let the mullahs win time via protracted talks which - as EU foreign policy chief Javier Solana himself grudgingly admitted - have so far led nowhere. As Prosor wrote in The Daily Telegraph ahead of Brown's visit, the international community "decided only to be undecided. Churchill used to tell the parable of the appeaser who feeds the crocodile, hoping it will eat him last. The world must send a message to Teheran that the feeding is over." We hope Brown will announce British support for a robust sanctions regime, implemented with a sense of urgency, as the only way to avert the devastating impact on regional stability that an Iranian bomb would bring. BROWN, WHOSE goal is to advance the "peace process," visited Bethlehem on Sunday, where he presented Palestinian Authority President Mahmoud Abbas with a new aid package worth $60m. Unfortunately, he parroted conventional EU wisdom, which assumes that the road to progress is paved only with further Israeli concessions and requires condemnation of the life-saving security barrier. Nothing could be more counterproductive. Brown will advance the cause of peace if he urges the Palestinian Arabs to, once and for all, renounce their demand for a "right of return," which would inundate the Jewish state with millions of Arabs refugees. They must find a home in the Arab world or in a Palestinian state created to live side by side in peace with Israel. He could further promote peace by telling the Palestinians that there can be no going back to the 1949 armistice lines and advising Abbas to prepare his people for these realities. Brown's statement in Bethlehem that "settlement expansion has made peace harder to achieve" was unhelpful. What has made peace harder to achieve is Palestinian intransigence at the negotiating table and mindless Palestinian violence elsewhere. Britain would also do well to reject the moral equivalence many in the West have drawn between settlements and terrorism. And its prime minister should know that no "freeze" can be applicable to Jerusalem or the strategic settlement blocs - where undermining the Israeli consensus on vital security needs would set back the prospects for progress to a viable accommodation. On bilateral relations, we are grateful that Brown has condemned ongoing attempts to punish the Mideast's only center of genuine academic and intellectual freedom by means of threats of academic boycotts. He could do even more: Let him speak out against the Orwellian predilection of many in the British media and intelligentsia to deny the inalienable right of the Jewish people to a secure national homeland.