One might be able to understand the clearly political reasons that led Eli Yishai - Shas chairman and minister of industry, trade and labor - to call for a national unity government yesterday at the Shas faction meeting. After all, he has repeatedly threatened that his party would vote no-confidence in the government if it continued the peace talks with the Palestinians. He instructed Shas MKs to abstain in yesterday's no-confidence vote initiated by the National Union-National Religious Party, and in the end Shas voted for the government "in light of the national emergency situation."

The demand to establish a national unity government thus stems from the complicated definition that enabled Yishai to remain in the government, and from his desire to once again see Yisrael Beiteinu, which left the coalition for political reasons, back in the cabinet, along with other right-wing parties. Yishai hopes they will all hold back the moderates in Olmert's cabinet, and prevent the prime minister and foreign minister from pursuing any sort of talks with the Palestinian Authority.

Shas is playing a cynical game. On the one hand, it is assuring its uninterrupted presence in the coalition by means of benefits and budgets. These range from reestablishing the dispensable Religious Affairs Ministry to projects such as "livelihood with dignity," intended as job training for yeshiva students but which have yet to produce impressive results. On the other hand, Shas has not stopped threatening to leave the coalition if the question of Jerusalem is placed on the negotiating table with the Palestinians.

Yishai now also argues "we should have stoped negotiating, not the other side," and calls on us to "strike at the terrorists with all our might and chase them down to the last terrorist." It is strange to hear these calls for an all-out war from someone whose rabbis are increasingly preaching the values of the separatist, ultra-Orthodox Lithuanian Jewish stream that prefers the yeshiva to army service and a working life.

Shas has come a long, bad way since the days it joined the Rabin government under Aryeh Deri. The populist, young and vibrant movement at that time represented - except for a hard core of full-time Torah students - hundreds of thousands of traditional Israelis from all walks of life. Its spiritual leader, Rabbi Ovadia Yosef, dared at that time to reiterate the courageous and unpopular view that in exchange for true peace, approved by the security establishment, occupied territory could be given up.

Since then, Shas has continually adjusted its positions to the most populist and hard-line stances of the right. It seems to be competing with the harshest opponents of political compromise. At the same time, it is distancing its voters from the Israeli mainstream. It seems that Yishai sees elections on the horizon, and has thus chosen to forgo a responsible stand, preferring to weaken the government at its most difficult moments. But Shas knows full well that it has much to lose on the opposition benches, and it is doubtful that its tough declarations will be backed up. This being the case, the prime minister would do well to respond with equanimity to Shas' latest verbal exercises.