There's something else I'd like to throw out about brainwashing and, judging by Q's posts, I'm pretty sure he/they know it to be true, too.
True Christians are impervious to the kind of brainwashing that conditions non-Christians.
Their faith in God, Creator and Saviour, in his words and works, and the indwelling of the Spirit of God, insulates them from external mind control as they have willingly submitted to the Holy Spirit - the Spirit of Truth - the almighty God and submit only to His guidance.
John 14:17
"Even the Spirit of truth; whom the world cannot receive, because it seeth him not, neither knoweth him: but ye know him; for he dwelleth with you, and shall be in you."
And:
1 Corinthians 2:15-16
…15The spiritual man judges all things, but he himself is not subject to anyone’s judgment. 16“For who has known the mind of the Lord, so as to instruct Him?” But we have the mind of Christ.
It is for this reason that Christianity (TRUE Christianity, that is) is hated above all religions by those who are "of their father, the devil." Those who belong to Jesus Chrsit are sealed and protected by the Holy Spirit and cannot be subverted.