I was focusing on the second half of the sentence, but now that I look at it, that "wanted" is a very strange one.

Sorting that bit out:

(Last week,) I wanted to ask you what your beliefs were (in the 90's) about...
(past wanting, past beliefs-- both may be over)
This is all standard, face-value.

OR

(Having now looked at it for the first time) I feel as though it is a "meek mood". I consider it more of a mood than a tense, but I don't think it occurs anywhere but present tense (while looking like the past tense). In some ways it's more like a tenseless passive construction.
It's as if the speaker is presenting the (in this case: ) wanting, as having been a past event in order to... Well, for some reason/ somehow add politeness... Perhaps the "distancing" from the act it used to mildly separate the speaker from their ~emotions~ (not sure if that's the best word for it). Perhaps separating from their own words and/or the conversation itself
For whatever reason, "I (right now) want to ask you what your beliefs are about..." has become too forward a phrasing.


(Hi,) I (just) wanted to ask you what your beliefs were about...
(meek-present wanting, meek-present beliefs)

*Putting in a word like "today" seems to snap the construction, possibly because one then notices how strange it is

"Excuse me! Sorry to bother you, I was just wondering if you wanted(would like) to see a movie with me some time."
Perhaps similar to -бы хотел- in Russian.

It's strange... Almost as if it really is a past tense that's just referring to twenty seconds ago. [for instance, just before the conversation started]

I've got it. It's about rejection of emotions. If you distance yourself from the wanting, then, if the person, say for instance, really doesn't want to answer any questions about their beliefs right now, then they won't have just stomped on your wanting. Compare:

-"I want to ask you what your beliefs are about..."
-"No." = deliberate negation of what the first person currently 'wants', as they said


-"I wanted to ask you what your beliefs were about..."
-"No." = only crushed a 'past' desire

This is why "just" so commonly goes with this construction, because the speaker is trying to minimize the scale of their wanting/question-asking as a whole, so that the possibility of rejection is easier on both the rejecter and rejected. Also why it shows up so much when asking out on dates, or impromptu public requests of strangers.