Your right
"You have read liberals sooooo wrong. If you think that Americans would let Mexico -- no, not even Mexico, Mexican separatists -- take several stars off the flag without so much as a voice raised..."
Many liberals would probably voice moral support for them, while others would be more proactive in their support. After all, they are just taking back what the US took from them in a war of aggression. Their is a substantial mindset within the left which despises this country and would like nothing more than to see it weakened or destroyed. Just look at the apologists for 9/11.