More Palestinian children killed by Israel in last 3 weeks than Israeli soldiers killed in military operations since 2006

It's hard to keep count of the number of times a cease-fire has been proposed, or rejected, or broken, or accepted for a limited time and discarded.

In the escalating conflict between Israel and Hamas in Gaza, it's been exceedingly difficult to get these parties to stop firing at each other for longer than 12 hours at a time.

Israel's relentless military assault on Gaza continues, and Hamas keeps firing rockets and sending fighters through tunnels into Israel. 56 Israelis have been killed in the fighting, almost all of them soldiers.

But nearly 1,200 Palestinians - mostly civilians - have been killed, according to the United Nations.

CNN's Jake Tapper asked Israeli government spokesman Mark Regev about the horrible human toll the conflict is taking on both sides.