I don't know how to say this respectfully, but how is this any different than a young adult attacking a Muslim, or black, or Asian, or Liberal, etc. Why are Jews special? What makes you a Jew? What are people anti against? Specifically?
Ask any young person what Jews do and you will NOT get classic antisemitic reasons 1) deceitful 2) killed Chris 3) drink blood of babies, etc.
What you see, I believe are young people who have nothing to believe in so believe in hate--and they take their pick of the above. My guess a young antisemite today would just as soon attack an Asian or Muslim. But you're looking at it through old lenses. You're not standing back and looking at youth rage objectively. And your very focus on your (sorry to say) selfish antisemitism first view, creates more antisemitism because you're actually focusing their attention on you when before you were just one of many hateful groups.
The problem is a break down of social values. Antisemitism is just one part of it. I'd be more afraid to be an Asian or Muslim in the West than a Jew. (though Israel is trying to even that up right fast).