This thread shouldn't even be about Israel, but for the benefit of people who don't have the slightest empathy, and can't put themselves in Israeli Jews' shoes even for a second, let me spell it out for you.
The year is 1936. You live in Germany. Adolf Hitler is Chancellor. If you own a shop, it is marked with a yellow star so that non-Jews know not to buy from you. Your children probably aren't allowed to go to the local school.
Maybe you manage to escape to Mandatory Palestine (before the British closed that escape route). Maybe you go into hiding for 4 or 5 years, never seeing the sun. Maybe you are sent to a concentration camp but survive. Either way, most of your relatives are slaughtered.
In 1945, you are finally freed. If you have been in a concentration camp, you are now in a refugee camp - you can't go back to your home as non-Jewish Germans are living there. Do you want to stay in Europe, among the people who slaughtered your parents, your grandparents, your cousins, your siblings, maybe your children?
You don't. You want to be among your people, who know what you're been through. Britain promised in 1917 that it would create a Jewish National Home in Palestine. That is where you want to be.
By 1947, the situation in Palestine has deteriorated rapidly. The Arabs are angry at the influx of Jews - and who can blame them - inter communal violence increases, and Britain gives up, handing the matter to the UN to resolve.
The UN decides the only solution is to partition the land. Is it a perfect solution? No. But is it the only possible one? Yes.
Do the Jews accept it? Yes. Do the Arabs? No. They want the whole land. They aren't willing to share. Arab governments invade, attacking a people who have just survived a genocide. But they are defeated by the Jewish army, who in the process take more land than the UN partition plan allocated to them - why? Because the UN proposed borders were not defendable - they divided both the Jewish and the Arab state into three separate parts each.
Israel did not start the war - it was attacked. It needs to make sure it can defend itself in the future. If the Arabs hadn't tried to take more land than they had been given, there would have been a Palestinian state in 1947. The Jewish people have just seen 6 million of their friends and relatives slaughtered like animals. They are going to do what they need to do to defend their only chance at a Jewish state.
In the process, many Palestinians are displaced and end up in other Arab states. Do those states grant them citizenship and allow them to work? Nope. They leave them stranded in filthy refugee camps.
After 1948, Jordan takes control of the West Bank, granting all those who live there Jordanian citizenship. Egypt takes control of Gaza.
So the people in the West Bank and Gaza didn't have a Palestinian state, but they were part of two Arab states. That could have been ok.
But in 1967 the Arab governments, led by Nasser, decide again to try and destroy the world's only Jewish state. The Egyptian troops invade from Gaza, and the Jordanian troops invade from the West Bank. When Israel defeats them in 6 days, occupying those territories in the process, what is it supposed to do? Give them back and open itself up to another invasion?
Of course, it is terrible for all those who live under occupation. But if Israel relinquishes control of those territories, it would be catastrophic for Israeli civilians.
Jews have been expelled from over 1000 cities and countries over the last 2000 years. Whenever a country has a problem, we were always the first to be blamed. Anti-Jewish violence didn't start and end with the Holocaust - pogroms have been a fact of Jewish life for millennia.
Israel has to win every single war. If the Arabs win one war, then Israel will be no more and Jews will have no place in the world where we know we are safe.
In 2005, Israel removes all its settlers from Gaza. The response? Rockets pouring down on civilians across southern Israel. Do you seriously think Israel can risk withdrawing from the West Bank after that experience?
IF the same thing happens in the West Bank that happened in Gaza, then nowhere in the whole of Israel will be out of range of rockets. Nowhere will be safe.