The Gazans have lived in their own self governing area since Oslo over 20 years ago. Israel has no claim on the territory. All that Israelis want is for the Gazans to get out of their lives. As a result Israel has established controls over import to Gaza. Most any thing can go in but has to be checked. Only weapons are not allowed (reasonably) and dual use items, like cement, have to be checked to make sure they have a proper end use.
Hamas runs a theocratic Jew hating regime that constantly attacks Israel. Suicide bombers, rockets, attack tunnels, mass riots to breach the fence. This is self destructive behaviour. Two Fridays ago a Gazan mob attacked their own side of the crossing to Israel. They returned last Friday. They blew up the gas line and the freight conveyor belt. As a result vitally needed gas cannot enter Gaza. Nor can regular supplies. Only a few trucks with essential medical supplies can now get through.
This is not the first such thing. In the last Gazan war they aimed rockets at the Ashkelon power station that supplied THEM with half their electricity. They failed but took out two of the 9 power lines into Gaza. And then attacked the Israeli electricity company workers who came to fix them.
When the final settlements were evacuated about ten years ago, Israel left a complex of greenhouses and irrigation systems that could be used by the Gazans. They were immediately stripped and made useless.
This is a culture very different from mine and yours. Where becoming a victim or a martyr is a success. I have no idea how this is going to be resolved.