I know KF ain’t the best place to ask religious questions but what is the Christian way to handle this? How can good fight against such blatant and militant evil?
It honestly depends on when you asked the Christians. The Crusades were trying to get Jerusalem out of muslim hands, the inquisitions were an effort to ensure heresy wasn't being taught.
This is something entirely different, and first we have to ask is whether they are Satanists or if they are "satanists". Capital S Satanists truly believe in Satan and would be the people still doing child sacrifice for earthly power, or attempting to use demonic power to do something evil. "satanists" are reddit tier atheists who follow Anton LeVey and only view Satan as a metaphor in a philosophical way. These guys can do whatever they want, and are likely the people doing lawfare to put Baphomet statues up next to the ten commandments because they think it's funny.
Capital S Satanists are the scary ones. You have to zoom out a bit, but if we are in a reality where there IS spiritual warfare between angels and demons (or even just good and evil forces in general) what is a normie going to do against someone with actual demonic power? I've read accounts where Satanists ask a doctor to will one of his children's soul to them in exchange for money. Not physically, just spiritually. After this, his daughter starting being attacked and overwhelmed with suicidal thoughts and evil pressure until he came clean to his wife and they severed the "spiritual contract" with the help of a priest. This happened in Rome, by the way. The reason it worked is that the spiritual head of the household is the father, who has spiritual authority over his family. This is why in Genesis there is such importance placed on the blessing a father gives his son.
Demons have to respect this because unlike humans who can ignore spiritual realities, they are entirely spiritual beings and know their place in the hierarchy. If they are attempting to attack your children with spiritual power, you can only defend them with spiritual power. Where do we get spiritual power? From Jesus, but day to day, from continually using our spiritual muscles through prayer.
So we can't pull another Inquisition (because Christocracy isn't how society runs these days) and we can't just kill them, but we can use prayer - a "useless" option for those who don't believe, but for those that do you can read accounts from saints throughout history where prayer has changed reality for people. My favorite example of this is Saint Faustina praying for Poland and for mercy, and Jesus appeared to her to ask her to stop her fervent prayer for the country as what was going to happen could not be held back any longer. It heavily implied that her prayers delayed WWII, or at least the invasion of Poland.
Prayer has power, but it isn't like asking a demon to do something. It's asking He who holds the universe in existence to affect it out of love for us, hoping He will do it, but accepting His will if He doesn't. Spiritual warfare is unfortunately real.
TL
R God holds the universe in existence, everything happens by his permissive or explicit will, so praying to Him to fix it is the most powerful thing we can do.
