This is why Tor and onionland is a lawless wild west. All so that journalists can report and trade documents, and so that repressive regimes can't easily censor access to news and information. This is the cost of encryption: you get all sorts of scoundrels in the mix in the name of privacy and security for the masses. Some might say this cost is too high: that scoundrels are running rampant and won't stop their criminal actions. But without this we get a broken backdoored Internet where no such privacy/security exists and could actually cause more damage to society since spying would be rampant.
Not to mention that for counter-intelligence the clues aren't the contents of a message but who is contacting whom, when, how often, and from where, most all of which can be determined from network traffic monitoring even if the contents of the message can't be read. In fact, if someone who shouldn't be contacting someone in China/Middle East/etc is doing so using encrypted data, getting a search warrant should be easier. Requiring back-doors to encryption is just laziness on the part of Law Enforcement.
May I ask what’s your background in law enforcement or the intelligence community, or in counter-intelligence specifically?
References to support the claims would also be helpful.
Sorry if that came across wrong. I may have misinterpreted the comment as being from the perspective of someone with work experience in these matters.