Israel confronts increasingly virulent worldwide challenges to its legitimacy.  An expanding chorus of politicians, journalists, academics, and Israel-haters relentlessly denounces the Jewish state as a racist apartheid abomination.  Any resemblance between their shrill diatribes and the persistent rhetoric of anti-Semitism during the past two thousand years is not coincidental.

Legitimacy problems are not new to Israel.  Few people remember that the Jewish state was born amid its own internal legitimacy crisis, with lingering reverberations that may yet determine its future.  In June 1948, six weeks after declaring independence, Israel confronted internal conflict that raised the specter of civil war.  Surrounded by invading Arab armies, the fledgling Jewish state seemed on the verge of reenacting the 1^st-century tragedy of fratricide that had terminated Jewish national sovereignty for two nearly thousand years. 

To Prime Minister David Ben-Gurion, the arrival of the Altalena -- a ship that sailed from France with desperately needed munitions and fighters -- was the spearhead of a right-wing putsch to overthrow the government.  Alleging a menacing challenge to the state and to his own authority, Ben-Gurion seized the opportunity to quash his detested right-wing political opposition, led by Menachem Begin.

The festering, and occasionally violent, hostility between these rivals could no longer be contained.  Four years earlier the Saison, the infamous "hunting season," forced  Begin into hiding while Irgun leaders were arrested, even tortured and deported by the Ben-Gurion provisional government.  The prime minister remained determined to act forcefully against his political rival. 

The Altalena arrived with Ben-Gurion's permission at Kfar Vitkin, north of Netanya.  There had been disagreement over the distribution and storage of munitions, but through their aides Ben-Gurion and Begin had reached consent that 20% of the weapons would go to Irgun fighters in Jerusalem, outside the proposed UN partition boundaries.  Unresolved disagreements persisted over storage of the remainder, with Begin wanting at least some designated for Irgun units in the Israel Defense Forces and Ben-Gurion insistent that they all be turned over to the IDF.

Rather than continue negotiations, Ben-Gurion ordered his soldiers to open fire.  Begin commanded his fighters not to shoot and the Altalena sailed to Tel Aviv where it ran aground offshore.  The next afternoon cannon shells (from what Ben-Gurion would call the "holy cannon") destroyed the ship and ended a two-day battle in which nineteen Jews were killed by their Jewish "brothers." 

The Altalena remains a sorrowful reminder that groundless hatred -- condemned in Judaism ever since the destruction of the Second Temple in 70 CE -- tormented the Jewish people even at their wondrous moment of national rebirth.  That doomed pariah ship still resurfaces occasionally from buried memory to roil Israeli politics.  On the political left there are Israelis who claim that Menachem Begin's Irgun received what it deserved for daring to challenge the authority of the State.  For the Israeli right, however, Ben-Gurion acted with ruthless determination to delegitimize, if not destroy, his despised political opposition.

Israel's internal legitimacy problem now focuses on Jewish settlers in the West Bank, biblical Judea and Samaria.  Some rabbinical authorities have justified military disobedience in response to settlement evacuation orders from the government -- citing the precedent of conscience-stricken Israeli soldiers who disobeyed orders to fire on Altalena fighters, their own "brothers." 

Some religious soldiers have been discharged or jailed even for expressing opposition to settler expulsion.  Others (following the precedent set by thousands of secular Israelis who refused military service during the first Lebanon war) have indicated their unwillingness to participate.  It seems inconceivable that Israeli soldiers would -- ever again -- shoot fellow Jews.  But the Altalena precedent hovers over the Jewish state as a perennial reminder of the tragic possibility of internecine Jewish violence.

The current crusade to delegitimize Israel as a racist apartheid state occupying Palestinian land has become an international obsession.  Pressure from the United Nations (and the Obama administration) to relinquish "land for peace" is unlikely to relent.  But any attempt by the Israeli government to expel tens of thousands of Jews from their homes, effectively undermining religious Zionism by eradicating its geographical base, could be catastrophic. 

Secular and religious Israelis have been unable to agree upon terms of Zionist unity, ideological or geographical, that will finally resolve their enduring, often acrimonious, struggle over internal legitimacy.  Should that scenario unfold Israelis may confront, yet again, the wrenching choices of 1948: When must political decisions and military orders be obeyed?  When is disobedience justified?  Who decides?

There is the ominous potential for a confrontation that would make the bloody battle over the Altalena, which erupted sixty-three years ago on June 21, 1948, seem like a minor historical blip.  In Israel, once again, Jews could become brothers at war.

Jerold S. Auerbach is the author of Brothers at War: Israel and the Tragedy of the Altalena, published in May by Quid Pro Books.