Legal status of Indian Reservations and CDA

If I remember correctly, are not American Indian reservations considered 
qusi-sovergin states under the law?

If this is true, what would stop me from negotiating with some tribe to 
establish an ISP on the reservation and then placing whatever material I wanted 
on that site without fear of reprisals from the US goverment.

After all, if they are a soveign state, decency is covered by whatever laws 
they have, if any, not the CDA.

If this is true, the Indians get the benift of having state-of-the-art 
telecommunications in thier communities, plus residual job creation, and 
everyone else gets freedom of speech.

Any comments?
Regards,
Michael Peponis
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