Jews are chameleons. Their history of being expelled from various nations shows they must adapt and improvise. Probably why they have the gift of gab (see: pilpul) and are willing to racemix themselves (much more than other races do).

The mixing allows them to blend in a little longer before their neurotic behavior betrays them. I suspect the culture of male circumcision in the West is another way for them to blend into the crowd.

Except, you have certain ones openly wearing the yarmulke or other obvious gear, so they're not all cryptokikes - but there are plenty who hide. See the phenomenon of changing ones last name to sound less Jewish.

Anyway, they're such charlatans and shape-shifters, often lying or at least stretching the truth to get the upper hand, perverted and sneaky. Of course they'd hate themselves. So they hate anything pure, that stands out to remind them what they're not and will never be - no matter how many goyim they bamboozle. So of course they want to corrupt that. 
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