A person makes a decision. If that decision is almost certainly going to result in the deaths of children, it is the wrong decision. You will never face a simpler moral scenario than this.

It sounds like you're suggesting that Israel should let Hamas kill Israeli children and civilians uncontested because they are hiding behind their own. Long-Term/big picture, I fail to see how that improves anyone's safety besides Hamas.

People can argue about justifications in good faith, of course… although ironically in this case, we can’t even do that, since we both know that bombing Gaza to the tune of 90% civilian casualties does nothing to ameliorate the conflict and everything to exacerbate it.

• As far as I know, the only casualty figures we have so far are from Hamas, and recent analysis seems to indicate that they are not credible.
• According to figures I've seen,
  Israel's civilian casualty rate is significantly lower than 90%. 90% is the average for civilian casualties in urban combat scenarios involving explosives, according to the UN.

Also, this isn’t a war. Wars are fought between nations, and Israel does not recognize Palestine’s sovereignty. Gaza has no self-determination. There’s no government. It is a prison full of children. An abomination that nobody living in Gaza created, perpetuated from outside.

A nation is different than a country, afaik no one disputes that Palestinians are a nation, but its statehood is hotly contested.

According to Google:

Nation: a large body of people united by common descent, history, culture, or language, inhabiting a particular country or territory

Hamas is the government of Gaza, they were elected and bafflingly and unfortunately they still experience widespread support from Palestinians. If elections were held again today, Hamas would win.