>I am preserving my culture. Why is it they can spread
>theirs but I am a demon for holding on?

You're not being criticized for holding on to your own, unique culture. From what I've seen, you're being criticized for viewing the presence of other cultures as being a threat to your own.

>They are however comming as a result of it's engineering.

Not really. Quotas for legal immigration may have risen somewhat in the last 40 years, but if the only immigrants were legal immigrants then we wouldn't even be having this conversation. Those who immigrate illegally aren't doing so because of a secret Aztlan plot, they're immigrating because doing so increases their standard of living.