You can use that rationale to justify any invasion against a weaker nation. All it takes is the lack of morality to justify horrific crimes. Your logic falls flat on its face in cases where force and coercion end up having the opposite effect than your stated goal. Countries in the Middle East are finding themselves more and more inclined to do business with China in times of increased threats and sanctions from the US. The "Great Satan" is hated by the population exactly because of the "diplomacy" that you advocate for. An increased resentment among the population influences politics, which drives these countries closer to enemies to the US.
if we withdraw our support, Israel will lose any incentive to stop the killing. More will die. And that would be the best case scenario.
So if Zionist government officials don't steal taxpayer money in order to fund their Zionist invasion of the Middle East, Israel will kill more people. So Israel must be supported in order to kill less people. Nice logic.
A cornered rat can only do so much before it gets exhausted. It's better to corner a rat and have it rage rather than pouring in all its cousins to make it feel safer in order to pacify it.
I have to point out that your "diplomacy" perfectly aligns with the Zionist project, which does involve a genocide as has been documented time and time again.
I don't like to attack the person besides the argument, but in this case I don't think you deserve the benefit of the doubt because of your colossal lack of empathy and unwillingness to consider solutions that don't involve supporting a full-scale invasion. What's more disgusting than an overtly wicked individual is one who hides behind talks of nuance and who uses fancy deductions (with false premises) in order to put wool in front of people's eyes.