I think if Tijuana was under military and civilian blockade for 2 decades, with a nominal "autonomy" that involves anything but actually allowing any meaningful development (a port, electricity etc), and with the American navy openly attacking and murdering anyone who tries to help (like with the flotilla attack)... even Americans would probably not be surprised if said city wouldn't be super peaceful. And even America would've been condemned by Europe or something for even doing all of those things I listed above.

Especially if the US was already promoting and military enforcing colonization of more peaceful mexican territory around Tijuana lol