Israelis and Palestinians were already in a state of uncertainty - the peace process yet again on hold until Israel's elections in May.
And now the death of the Jordanian monarch, affectionately code-named PLK by State Department officials - the Plucky Little King - magnifies the sense of unease about what lies ahead without the pivotal, moderating influence of King Hussein.
And the last-minute appointment of his eldest son, Abdullah, as his successor creates a new uncertainty where the only major variable had been which Israeli party is in power.
While their neighbors across the puddle-thin Jordan River mourned their king with tears that seemed more akin to grief for a loved one than a ruler, Israelis and Palestinians felt the loss in different ways.
Israelis lost the first Arab leader in whom they felt a sense of warmth and trust. They worry whether the relative stability Hussein created next door can be maintained by his son.
And Palestinians - many of whom held a grudge against Hussein for losing the West Bank to Israel in 1967 and then opposing Palestinian nationalists operating in Jordan - largely forgave him and now have hope King Abdullah will be even more sympathetic to their cause.
Israel has never mourned an Arab leader the way it is marking the passing of Hussein. Flags were flown at half-mast during the funeral, and teenagers lit candles in the shape of a peace sign in Tel Aviv's Rabin Square - the plaza named for slain peacemaker Yitzhak Rabin, who was assassinated in 1995. One Hebrew newspaper ran an unprecedented headline in Arabic reading "Goodbye, our dear friend."
The quintessential Israeli image of Hussein - broadcast over and over on television - was of his visit to the seven families whose daughters were killed by a Jordanian soldier in 1997. One of the mothers he visited gave birth Feb.7, the day Hussein died, and named the baby in his memory, Yarden - the Hebrew name for Jordan.
But foreign ministry and intelligence officials say they were taken off guard by Hussein's last-minute decision to remove his brother Hassan as crown prince and instead appoint his son Abdullah, young and largely unknown in diplomatic circles.
Foreign ministry officials say Abdullah will try to carry on his father's legacy of peace, and that the new king seems to be gaining wide Jordanian and international support.
But still there are concerns here that Abdullah could bow to popular sentiment in favor of cooling relations with Israel. Jordanians often complain they have seen few real dividends from the peace process, but Hussein's unique authority allowed him to defy critics in Jordan and the Arab world.
Recognizing the difficulties Abdullah may have in wearing the same mantle, President Clinton pledged $300 million in support and promised the world would support a rescheduling of Jordan's debt. Abdullah inherited a nation with high unemployment and a million Palestinian refugees.
Egypt as regional broker
The role of a regional power broker in times of crisis may now go to Hosni Mubarak, the Egyptian president whom Israelis see as much more firmly in Palestinian leader Yasser Arafat's camp. It was Hussein who was invited to join the Wye peace talks last October, not Mr. Mubarak.
There are also concerns that Jordan's leadership change may be used by the right wing in Israel's election. Prime Minister Netanyahu's Likud Party has often made the instability of Arab nations a cornerstone of its case against trading land for peace.
More than half of Jordanians are of Palestinian origin and most Palestinians have family across the border - but signs of grief in the Palestinian territories have been subdued to nonexistent. Mr. Arafat declared three days of mourning, but expressions of sorrow seen in Jordan have not materialized here.
That is in part due to Palestinian ambivalence toward Hussein, and his historic rivalry with Arafat. In 1970, the Palestine Liberation Organization began building a "state within a state" in Jordan, challenging the king until he squelched Arafat's guerrillas. Years later, however, Hussein redeemed himself in Palestinian eyes by supporting their quest for statehood and showing some support for Iraq.