This may help explain some of what is going on:
The Israel Air Force used a new bunker-buster missile that it received recently from the United States in strikes against Hamas targets in the Gaza Strip on Saturday, The Jerusalem Post learned on Sunday [last week].
The missile, called GBU-39, was developed in recent years by the US as a small-diameter bomb for low-cost, high-precision and low collateral damage strikes. Israel received approval from Congress to purchase 1,000 units in September and defense officials said on Sunday that the first shipment had arrived earlier this month and was used successfully in penetrating underground Kassam launchers in the Gaza Strip during the heavy aerial bombardment of Hamas infrastructure on Saturday. It was also used in Sunday's bombing of tunnels in Rafah.
The attack on Gaza may be a test-run for Iran's nuclear sites. In that case, what we may be witnessing is Israel's initiation of full-scale war with Iran. That would certainly make as much sense as the current stated rationale for invading Gaza.