History is a narrative. It is an interpretation. It is an explanation and it is always based upon what 'facts' and 'opinions' the historian choses to utilize. You are correct in your analysis of how historians examine, consider and utilize those 'facts' that are recorded for their examination. And you are correct that students should be taught to think critically, understand the nature of the sources, and their substance. There are few 'objective' facts ever. Because what 'facts' are recorded, and the context in which they are recorded are not 'objective.' The war between Palestinian Arabs and Jews started in 1920. It became a war between Israelis and Palestinians in 1948. There were great wrongs on both sides and great suffering. Anyone who knows anything about events in 1947-1948 understands that Palestinian Jews, and then Israelis were faced with extermination. Anyone who knows anything understands they were assailed first by well armed local resistance and later invasion by many nations. Anyone who understands anything also knows that Israel was split between ruthless and those who only did what was necessary. The ruthless sought to drive ALL Arabs out of what the Revisionist saw as Palestine, and those who did only what was necessary often drove Palestinians out to secure lines of communications and rear areas.
from the article: PA adopts textbook, banned in Israel, offering both sides' narratives