The Israeli calculation here seems to be that Abbas is preferable to Hamas, when all that is actually certain is that he is publicly less bellicose. It is also unclear whether he holds any real power, and can restrain Hamas in any meaningful way — and whether he really wants to. From the TimesOnline, with thanks to all who sent this in:
A HAMAS plot to assassinate Mahmoud Abbas, the Palestinian president, has been thwarted after he was tipped off by Israeli intelligence.
Hamas”s military wing, the Izza Din Al-Qassem, had planned to kill Abbas at his office in Gaza, intelligence sources said.
Abbas, who became president of the Palestinian Authority last year after the death of Yasser Arafat, was formally warned of the danger by the Israelis and cancelled a planned visit to the territory.