First, I would point out that the land in question belonged to the Arabs in the Middle Ages only because they conquered it from the Romans who had conquered it from the Jewish population in 70 C.E. (A.D.), who had lived on the land for thousands of years.
Second, in 1948, the United Nations attempted to establish two states, one Jewish and one Arab, on the land in question.
While the fledging Jewish nation of Israel accepted its 1/3 of the partition, the Arab population rejected its 2/3 and the two-state solution. Seven Arab armies then declared war and attacked Israel, only to be defeated and leaving a large Arab population stateless to this day.
Third, I would point out that the United States supports Israel because the Jewish state is the only true democratic country in the Middle East and has been one of America’s most reliable allies for over half a century.
Finally, I submit that there is no excuse for any group of people to cheer the destruction of the heart of an American city and the loss of over 3,000 of its citizens.