And do you think intelligence agencies aren't going to figure out a way to continuously improve their methods?
That's why Spycraft is a game of "Cat & Mouse". It's always a endless string counter-move upon counter-move.
That's to be expected.
But you see, once you start the process by allowing it on Starfleet officers and government employees it creates a slippery slope of precedent which can continue to be built upon. Does the Federation President's security protection detail begin employing telepaths to make sure there are no threatening people within the vicinity? Even when the President is among the public giving a speech? If that's allowed, then what about civilian law enforcement having access to telepaths when questioning suspects/persons of interest? Once that gets allowed, why not just go all the way and have permanent telepathic monitoring?
Let's go the opposite route, what if you're so paranoid about having your mind read that you banned Telepaths from living close to you or doing business with you?
Are you going to have a sign that says "No Telepaths Allowed"? Are you going to ban "Telepaths" from serving in your Government / StarFleet for fear of leaking secrets or stealing secrets?
Are you going to be like the Devore and hunt down Telpaths and outlaw Telepathy?
What about the Betazoids and their natural free reign to read everybody's mind without consent?
Don't forget that there are the Mari in the Delta Quadrant, an entire society that is telepathic.
That's part of natural society for them, if they can't read your mind, you're insulting them or hiding secrets from them.
That's a very bad example. Betazoid custom is to only read a person's thoughts with their consent, a fact Deanna was frequently reminding Lwaxanna of every time she read someone's thoughts.
Yet Lwaxanna constantly violated it all the time by reading another persons mind.
Don't forget, she's a high ranking diplomat.
Imagine what every other Telepath can do without you ever noticing.
There's also no greater invasion of privacy then having to share you inner monologues and thoughts with others.
So what are you going to do if you're surrounded by Telepaths?
Go buy that Telepathic Inhibitor? They're huge and bulky. If you don't mind wearing that ginormous contraption around your head, then be my guest.
Not granting them security clearance or limiting the job opportunities available to them just because they are of a species that can't be read telepathically goes back to my previous point, that they are being told what they can or can't do simply because of their genetics. Which last I checked is a stance Star Trek has always spoken out against.
So if the Government Interviewer / StarFleet Officer had the natural ability to read your mind as a applicant and made a request to read you as part of the interview process.
What do you say? Are you going to discriminate against them for doing what's a natural ability to them?
Trust that they aren't reading your mind and hope for the best? They may secretly read you anyways and you would never know.
If that happened, telepathy would no doubt be regulated to provide everyone with some measure of privacy. That's just basic decency.
And if there's no way to gurantee privacy? That mind reading can happen and nobody else would know it?
It basically takes a Telepath to detect another telepath, and if you don't have one, then any other local telepath can read your mind. What then?
They are people living as they normally live. They are not an employer/government forcing me to share my inner mind.
What if they are constantly reading your mind for funsies or as part of normal daily life since it's part of their nature and they can't turn it off?