Why did the English and Americans start conflict with Israeli-Palestinian?

Answer 1

The question is worded oddly, so it is unclear what it is asking.

1) Why did the English and Americans start a conflict with Israeli-Palestinians? -- This is incorrect. The English and Americans are not in conflict with "Israeli-Palestinians" (which is a meaningless term, just like French-Britons would be). As a result

2) Why did the English and Americans cause the Israeli-Palestinian Conflict? --

The English and the Americans did not cause the Israeli-Palestinian Conflict. The Israelis and Palestinians did that themselves. The British (of which the English are a large subset) created the Mandate of Palestine, which allowed for the creation of two polities. Those polities had strong nationalistic aspirations that opposed those aspirations in the other polity. The British did not inspire or support this divergence, but they did accept it without trying to reconcile the problems. The British wanted easy administration, not problem solving. However, since they did not cause the problem, it was not theirs to solve. Similarly, the US is the biggest supporter of both Israel and Palestine, so US funding is certainly helping to perpetuate the conflict, but US funding has nothing to do with the root causes. If US funding were to immediately cease, the situation on the ground would not become more peaceful.

The Israeli-Palestinian Conflict has its origins in the confrontation between immigrant Zionist Jews in the Mandate of Palestine and their interaction with the indigenous Arabs in the 1920s and 1930s. Before that point, the Immigration into the land had been a small trickle and Arabs were not terribly concerned. However, the Jewish immigration in the 1920s was quite large and disruptive. By the mid 1930s, both sides had developed militias which they used both to attack British colonial institutions and each other. Jews also flooded back to the Holy Land following World War II, since they felt that they would always be persecuted in countries where they were the minority. In 1947, as UN Resolution 181 was being debated, a full-scale war erupted between the Jewish militias and the Arab militias. When Israel declared its independence in 1948, the Arab States joined in the War which caused it to be internationally recognized and called the Arab-Israeli War of 1948-9. The on and off conflict that has remained unresolved for over half a century now.