Interesting analogy with US / Mexico. But I think you failed to complete it so I'll help out attempting to extrapolate the numbers as you have, apparently using a factor of around 34x (given that the population of the US is roughly 34x that of Israel)
Imagine that after the initial attack, the US response was to engage in a campaign of mass aerial bombardment of a densely-populated Mexican city.
Keeping with our 34x extrapolation, this city would have a population of 34x that of Gaza, or roughly 20 million.
Unfortunately, the analogy falls flat here, given the extreme density of Gaza. There is no city in Mexico that large, so we'll adjust and use the largest city in Mexico: Mexico City, which has a population of around 8.85 million.
The conservative estimates of the death toll in Gaza put the toll at over 30,000 or around 4-5% of the population. We'll be conservative and use 4%
In this hypothetical scenario, the US retaliates by killing 4% of Mexico City's population, or roughly: 442,500 people
That's roughly 147 September 11ths.
Remember though, we had to scale down and use a smaller city. The ACTUAL deaths if we just go off the estimated 30k+ scaled up to 34x (rather than 4% of a given city) would be well over 1 million!
That's roughly 340 September 11ths
So... if in response, the US engaged in an aerial carpet bombing campaign and killed the equivalent of 340 times the people that died in the 9/11 attacks ... or over 20x the number of people killed in the initial hypothetical attack, how would I react to that?
With absolute horror. That's how.
To put this in perspective, the combined death toll in Iraq and Afghanistan during the US 'war on terror' is estimated to be around 4.5 million.
https://www.washingtonpost.com/world/2023/05/15/war-on-terror-911-deaths-afghanistan-iraq/
This too is is tragic and largely unnecessary (and accomplished little in actually decreasing terror activity). But, that was over 20+ years of war. Divided out over 20, a rough estimate is 225k deaths a year.
So in the hypothetical scenario, it would be like the US killing in 5 months over 4x more than it actually did after 9/11 in 1 year.
The rate of death (fatalities per day) in Gaza in staggering. This is not to dismiss the pain of the Israeli victims, but countering an atrocity with another atrocity and humanitarian crisis over 20x the magnitude is outrageous.
"Israel's actions in Gaza may be excessive" is the understatement of the century.
As far as the "from the river to the sea chant", Israel uses this too. It's a campaign slogan of the ruling Likud party. Netenyahu has used it as too.
And don't forgot, the patriotic US song "America the Beautiful" ends with a similar line "From Sea to Shining Sea." Do Americans and Israeli sing/chant this with genocidal intent? Or is it just more of patriotic thing?
Of course, In the case of the US, the whole "manifest destiny" thing certainly did result in genocidal outcomes as far as the indigenous population goes. So maybe Americans are just as genocidal as Hamas for using this language and singing these songs?