Building towns/cities/settlements in Gaza and the West Bank and moving Arabs off the land that they once owned. In some cases tearing down dwellings or plain moving them out and moving Jews into the houses is a modern theft.
As for the formation of Jordan who cares. The following is directly what kicked off the Arab/Israeli conflict
Factors involved in the exodus include direct expulsions by Israeli forces, destruction of Arab villages, psychological warfare including
terrorism, massacres such as the widely publicized
Deir Yassin massacre[18]: 239–240 which caused many to flee out of fear, crop burning,
[19][20] typhoid epidemics in some areas caused by Israeli well-poisoning,
[21] and the collapse of Palestinian leadership including the demoralizing impact of wealthier classes fleeing.
[22]
Later,
a series of land and property laws passed by the first Israeli government prevented Arabs who had left from returning to their homes or claiming their property. They and many of their descendants remain refugees.
[23][24] The existence of the so-called
Law of Return allowing for immigration and naturalization of any Jewish person and their family to Israel, while a
Palestinian right of returnhas been denied, has been cited as evidence for the charge
that Israel practices apartheid.
[25][26] The status of the refugees, and in particular whether Israel will allow them the right to return to their homes, or compensate them, are key issues in the ongoing
Israeli–Palestinian conflict.