Vanilla Ice -- Cool Down, Native Americans ... Adam Sandler's Not Trying to Be Kevin Costner

Here comes the cavalry ... lead by Vanilla Ice, who's defending Adam Sandler against the Native American actors who quit his movie -- even though Ice says he's part Choctaw.

Vanilla Ice co-stars in Sandler's flick, "Ridiculous Six" .. and spoke to us at LAX about the actors who walked out last week, claiming the script is offensive to Native culture.

Ice says he's trying to see it from both sides -- because of his roots -- but added, "This movie isn't 'Dancing with Wolves' ... it's comedy"

He also talks about his role in the movie, which makes it crystal clear this IS 100% spoof.