Yes, it does seem to have long-term negative effects on still-developing brains. As far as "susceptibility to certain types of thinking associated with left and liberal ideas", I don't know. Maybe. College kids tend to be that way anyway.
If I try marijuana and lose my strong pro-life, traditional family, and Christian orientations, I'll let you know. At age 59 I doubt that is going to be the case. Not aware of any drug that would do this except for something like scopolamine that would make one extremely suggestible for a short period of time.
Your comments I think are well meant but rather specious.
If you were to begin smoking dope on a regular basis, it would definitely be due to a change in life and it would cause your thinking and worldview to change.
But given your life history and faith in Christ, it’s doubtful you’d fall apart like this.
BTW, scopolamine just puts one out if their mind for a large period of time at high doses. Not enough connection to reality is maintained for it to be used as you suggest.
But any drug can be used for brainwashing type applications.