This is a brief outline of the Israel story for people who haven't been keeping up.
My contention is this is all pretty simple in outline, so I'm keeping it simple... I'll probably post some further supporting material in the next few days.
Israel was founded in 1948 by edict of the UN. The rationale was that after their persecution at the hands of the Nazis the Jews needed a nation of their own.
The Palestinians are the people who were living there at the time. They call this event the Nakbah, meaning "the catastrophe".
(And now you know more than most people who watch television news.)
In 1967, Israel conquered adjacent territory (the "Six-Day War"), and since then they've been a rogue state by UN standards.
(And now you know more than everyone who watches television news.)
Gaza is effectively a large refugee camp, crowded with Palestinians displaced by Israel. They've been struggling to survive an Israeli blockade that was imposed after Hamas became the elected government in 2006.
(And now, we're way off the "mainstream" map...)
The American left does not call for the elimination of Israel, but rather for it to return to it's pre-1967 borders, aka the Green Line. Israel says those borders are "non-defensible", and has moved in "settlers" as fast as they could, which complicates any negotiations.
There's a monotonous pattern toward events in the Middle East: Negotiations collapse in out-breaks of violence, with lots of finger pointing. Sorting out whose fault it is often seems complicated, but left-wing observers such as Chomsky argue that the blame clearly rests with Israel and the US.
(And this is not a position you'll see discussed in the New York Times, let alone on television.)
You will then hear complaints about Israel's actions being a "disproportionate response", which is to say that they've killed a lot of innocent civilians again.
Israel gets a lot of money from the US to do all this: we fund around a quarter of it's military ($3 billion per year).
It would seem that nothing would be simpler than for the US to get Israel to tone-down it's act, but instead any successful American politician is required to recite a pro-Israel line.
That includes Hillary Clinton: as Senator of New York, she invited it's citizens to consider how they were feel if they were being attacked by Canada.
(If we're doing absurd analogies, I might ask how they would feel if New Jersey were blockading Manhattan... Or how they would feel if the UN had put Israel in Brooklyn.)
And why was a place of refuge for European Jews created in the Middle East? This has to do with "Zionism", a doctrine based on the biblical stories about the historical Israel. Why secular institutions like the UN and the US backed a particular biblical interpretation is another question.