It all depends, I guess, on whether the humans still remember the Shastinian occupation enough to be emotionally affected by it. As I've written it, humanity is in the latter half of the 21st Century, while the occupation occurred during the earlier half, which means a generation could have passed in between. I mean, sure, they'll learn about it in History, but unless some Shastinians stayed around to live peaceable lives on Earth, they'd probably just be some folks out there who persecuted Earth folks at some point, and that'd be the extent of it.
Of course, if there were still Shastinians on Earth after Earth's independence, I could see where the prejudice could sink in, so it's all a matter of how we write it, I guess.
