There is nothing more nauseating than watching people celebrate as rockets are being fired toward Israel from the Gaza Strip.
This is what happened last week when Hamas fired rockets at Jerusalem and Tel Aviv.
As soon as the sirens went off, many Palestinians took to the streets and rooftops, especially in Jerusalem's Arab neighborhoods, to cheer Hamas. Sometimes they responded to the Hamas rockets by launching fireworks into the air as a sign of joy, and chanting, "We are all Hamas!" and, "O Jews, the army of Mohammed is coming after you!"
Scenes of jubilation over the rocket attacks on Israel were also reported in several Palestinian cities in the West Bank, including Ramallah, the center of Palestinian "pragmatism and moderation."
Later, upon learning that Hamas's rockets had failed to kill Israelis in the two cities, the Palestinians voiced disappointment.
Never mind that the rockets could have fallen on their heads. As far as these Palestinians are concerned, there is no problem if a number of Arabs are killed on the way to destroying Israel.
The celebrations reflect the strong hostility that many Palestinians continue to feel toward Israel despite 20 years of a peace process, and billions of dollars of Western aid. This hostility is the direct result of years of anti-Israel and anti-Western incitement in the Arab and Islamic world.
The hostility is directed not only toward Israel, but also its friends -- above all, the United States.
Similar outbursts of joy had erupted in many parts of the West Bank, Gaza Strip and east Jerusalem immediately after Palestinians heard of the 9/11 terror attacks in the US.
And this was not the first time that Palestinians had expressed joy over the targeting of Israeli cities.
During the 2006 war in Lebanon, Palestinians and some Arab citizens of Israel took to rooftops to cheer Hizbullah's rocket attacks on northern cities in Israel.
During the second intifada, many Palestinians, particularly in the Gaza Strip, used to take to the streets to sing and dance and hand out candies after hearing about another suicide bombing inside Israel.
And when Saddam Hussein fired rockets at Israel in the early 1990's, Palestinians also took to the streets and rooftops, chanting, "O beloved Saddam, strike strike at Tel Aviv!"
Last week, by the way, many Palestinians in Ramallah, Nablus and Hebron were chanting: "O beloved Qassam [Hamas's armed wing], destroy, destroy Tel Aviv!" and "The people want the destruction of Israel!"
No one is expecting the Palestinians to express solidarity or sympathy with Israel in its confrontation with Hamas.
But when many Palestinians express their joy in public over the firing of rockets and missiles at Israeli cities, one is entitled to wonder whether there is a majority of Palestinians who would ever agree to any form of compromise with Israel.
In today's world of the Palestinians, anyone who talks about peace with Israel is a traitor and a collaborator; but anyone who calls for the destruction of Israel and fires rockets at Tel Aviv and Jerusalem is a hero.