Americans' ardent support for Israel is palpable in poll after poll showing far greater sympathy for the Jewish state than for Palestinians.

It's evidenced in the vote in the last U.S. Congress to top up American funding for Israel's missile-defence system: a lopsided result of 420 to 9.

So that American backing is not in question; it's a decades-long reality and was just reinforced with the blood-curdling massacre of Israeli civilians by Hamas militants on Oct. 7.

What's less certain is the reaction from one important constituency as Israel expands its counter-offensive in Gaza and as the death toll mounts among Palestinian civilians.

We're talking about the U.S. left. It's virtually the only place in American politics where there might be a debate — over what's acceptable in war, and about a path back to peace.

And signs are emerging of Democrats wanting to pressure Israel into abiding by certain limits in its operation.