Rockets have been fired from Gaza "across southern and central Israel, including Tel Aviv and Jerusalem, and the infiltration of Hamas militants."
Over 100 Israelis have died and more than 900 were injured after rockets were fired from Gaza by Hamas militants, Israeli officials said Saturday.
The Palestinian Health Ministry said 198 were killed in Gaza and at least 1,610 were injured Saturday in retaliatory attacks from Israel.
"We are at war. We will win," Israeli Prime Minister Benjamin Netanyahu said on Saturday.
The Israeli Defense Forces earlier declared "a state of alert for war," according to a statement issued by the IDF.
"Over the past hour, the Hamas terrorist organization launched massive barrages of rockets from Gaza into Israel, and its terrorist operatives have infiltrated into Israel in a number of different locations in the south," the IDF said early Saturday.
As Israel did their deeds outside internationally recognized Israeli territory - so outside the internationally recognized jurisdiction of their courts - hence were Israeli Law does not apply.
So those deeds were unlawful (no matter how much Israeli Law is rigged to say otherwise), and even by that twisted definition you selected of "terrorism" that defines it so that state-sponsered terror attacks on a nation's own soil do not count as "terrorism", Israel's military attacks on civilians anywhere outside the internationally recognized borders of Israel (so including Gaza) for the purpose of intimidating the population are still terrorism because the Law that does apply there says they're unlawful.
Sure, there is no such thing as the Geneva Convention and there are no such things as War Crimes and its all above board if the people controlling power in the country doing the deeds tell their parliamentarians to write down that "it's all legit!" in their own country's legislation.
War crimes are explicitly not terrorism by definition. If you need a basic high school education though there's hopefully a public school near you. This subject and topic is covered under civics.