I think a lot of Americans have a hard time grasping the idea of Jewish indigeneity because they dont know where their own ancestors came from. Maybe they'll have vague ideas like German, Italian, or Irish, but what they know has very little bearing on their day-to-day lives. They don't dress any different, they don't speak the language their great grandparents spoke, they don't hold regular ceremonies and rituals that harken back to the old days.
The idea of an ethnic group maintaining a constant identity over thousands of years is patently absurd to them. "You're telling me you're still mourning something the ancient Romans did? That's ridiculous! Clearly you've fallen for modern Israeli propaganda, otherwise you're deliberately arguing in bad faith in order to justify land theft and genocide!"
It's very frustrating, because when I say these things I do not say them in bad faith. My friend once said "it's a very American thing not to understand large timescales", and I think she was right on the money. The process of American assimilation has cut peoples ties to their ancestors to such a degree that they can no longer comprehend a continuous identity spanning millennia.
So I'm going to say this in the clearest language I can:
There is a genuine, historically provable, continuous connection from ancient Israelites to modern Jews. By the laws and customs of those ancient Israelites I am one of them. Let me reiterate. I am an Israelite, a Hebrew, like from the Bible, and the fact that my identity has been so mythologized and talked about as if it's a thing of the past will never change that.