Don´t bother with the tiny nationalists, think of them as derpy people who think too much of the past
What you should bother with are the big anarcho-liberal douchebags. Those will revolt.
High tariffs can mean many POPS without everyday or luxury needs, thus increasing militancy. It isn´t about taxes only. Am I correct? I seldom raise tariffs so I don´t recall for sure if tariffs also affect goods imported by POPs.
Yes, tariffs apply to pops also.
Looks to me like it might be time to enact some political reforms