Prime Minister Benjamin Netanyahu is sounding increasingly like a member of the post-Oslo Labor Party in his rhetoric, by emphasizing security and totally neglecting the subject of Israel's legitimacy. An over-reliance on security arguments has bedeviled Israeli hasbara efforts, leaving an entire generation abroad and at home without a clear notion of the Jewish right to the Land of Israel. In any battle between legitimacy and security for public opinion, Israel's genuine security needs will always be trumped by the elastic "legitimate rights of the Palestinians." Netanyahu told Charles Moore the former editor of the Telegraph, in a recent piece in that paper, that he worried about a Britain that had evidently forgotten the lessons of Munich. But it is Netanyahu himself who has misunderstood these lessons.

The architects of the Versailles treaty had provided Czechoslovakia with defensible borders, as Czech staying power was a keystone of French hopes of being able to deter Germany with the threat of a second front in the event of war. France and Germany sold out Czechoslovakia at Munich not because they failed to appreciate that they were depriving it of defensible borders. They appreciated that fact, but in the end chose to disregard it. Realists did not see the need to go to war on behalf of a faraway country and a people whom they knew nothing about. Idealists had bought into the notion that only by acquiescing to "legitimate" German demands could peace prevail on the Continent. Peace would provide security rather than the reverse - an argument currently resurrected by Oslo proponents and "genuine" friends of Israel.

Nobody is going to respect Israel's demands for security if the Arabs are allowed to get away with the argument that Israel's conception was in itself illegitimate. The idea that a peace of surrender provides security will further entrench itself unless Israel drops the gloves and exposes Palestinian aspirations for what they are: Israel's elimination as a state at best, and Itamar writ large at worst.

By emphasizing security ad infinitum, we will be fobbed off with ersatz security arrangements and, chiefly, a demilitarized Palestine. The latter will in short order resemble a "demilitarized Gaza" under Hamas, a "demilitarized southern Lebanon" as envisioned by UNSCR 1701 and, yes, a "demilitarized" Germany. Who (unless we are dealing with a situation resembling the Soviet Union vis-a-vis Finland in the period between the end of World War II and the demise of the USSR ) is going to deprive a sovereign state of the full exercise of its sovereignty within its own borders? Any country will eventually violate demilitarization agreements unless, like post-war Japan, it is content to abide by them, or is aware that it will pay a severe penalty for such violations.

An independent Palestine doesn't fit either category. Palestinian violations will be incrementally calibrated to dissuade Israel from using force and dismantling the "peace architecture" until the balance has changed irrevocably.

A second substitute for security arrangements will be hollow offers of external guarantees. International support is important, but Israel must be capable of mounting its own defense. Netanyahu has been too meek and gentle with the powers that pressure us for concessions, but assume no responsibility for their diktat. The guarantees are as sound as the Zimbabwe dollar, as the states offering them are downsizing their military strength due to a fear of budgetary overstretch. Barack Obama may symbolize the syndrome, but he is a product of an increasingly fatigued public opinion chastened by the protracted wars in Iraq and Afghanistan and fearful of overcommitment.

The reluctance to use force, as displayed in the case of Iran, has reasserted itself in Libya. We constantly hear about "muscular" sanctions that, if not circumvented, will still take years to bite. By that time the Libyan insurgents will long since have been mowed down by Gadhafi's planes and tanks, leaving his regime free once again to endow prestigious Western universities.

We returned to Judea and Samaria, the cradle of Jewish history, as the result of a defensive war in 1967. An accelerant to that war was the failure of the American guarantor to honor its pledge to preserve Israeli freedom of shipping. Then the White House occupant wasn't a coldly analytical Obama type, but Lyndon Johnson, a true philo-Semite. Unfortunately, America was at the time too preoccupied in Vietnam to honor its guarantee.

The Book of Esther, which we will be reading for the Purim holiday tomorrow night and Sunday, demonstrates that things don't change. When Queen Esther exposes Haman's plan to exterminate the Jews of the empire, she appeals to King Ahasuerus on humanitarian grounds and reasons of state (Haman does not care for the economic damage he is inflicting on the empire ). As Esther is an intended victim, King Ahasuerus is sufficiently irate to execute Haman, but protocol (perhaps he couldn't pass a UN resolution or secure NATO unanimity ) does not permit him to revoke the original decree allowing the extermination. The best he can offer is benevolent neutrality, by decreeing that the Jews are allowed to act in self-defense. Israel arose so Jews would no longer be dependent on half-hearted friends like Ahasuerus to act in their own self-defense.

The only way to convince others that we can be allowed to exercise this right is to reassert whole heartedly our claim to this land. As Deputy Prime Minister Moshe Ya'alon put it in his eulogy for the martyred Fogel family, whoever forgoes this claim will never enjoy security.

Dr. Amiel Ungar, a political scientist, is a regular contributor to Haaretz English Edition.