Think you’ve got some of this backwards. Royalty was far more concerned about aligning with the Church than the Church ever was about aligning with royalty. Take the Crusades, for example. Then look at Henry II & Henri IV, and even Henry VIII. Then look at the French Revolution where, indeed, priests, nuns, bishops were slaughtered along with aristos. Then take a look at Cardinal (”Prince,” as you say) Mindszenty, among countless other examples of standing up to power—royal or not.
And, as Aquinas (FR name) mentions, there are good and bad bishops, as there are good and bad politicians, kings, presidents, teachers, etc. How certain bishops behave or react has nothing to do with the tenets of their Church.
Backwards? I have seen little evidence of the Democratic party trying to align itself with the Catholic church or support its beliefs. To the contrary.
Leaders of the church, OTOH, have bent over backwards supporting the Democrats and their socialist programs. Notre Dame gave Obama, who supports abortion, an honorary degree. Georgetown allowed Obama, who supports abortion, to speak at the school and complied with demands to cover the crucifix! The bishops have openly and strongly supported the administration’s programs for illegals and socialized medicine.
The church should stay out of politics.