Tradecraft hasn't changed much. It has been fairly well tested. Operational security and information security have not changed much... They have become more difficult with cell-phones and small internet connected devices.

I think another big difference and a subject that probably would be included in a redo is understanding how all of the modern data generating systems can reveal covert activity through the analysis of metadata and how to "hide in the noise" of this.

The geospatial correlation of burner phone to actual identity if one does not practice good sanitation as far as locational security when accessing wireless networks as an example.

I treat my cellphone as though I have an always-on homing beacon on me that can not be trusted to be off even when it says it is off. And that's not even a smartphone, so I can still remove the battery if I want to. Now throw ANPR, face recognition, cheap DNA synthesis, ubiquitous video surveillance, public transport ID cards and a some more modern goodies into the mix and it takes real work just to move from 'A' to 'B' without leaving a trail a mile wide.

There is that, but there is also the massive palaver at Gatwick which reveals that the authorities aren’t actually very good with modern tech.

They aren't good. Hence the dragnet approach of collecting all data, and then waiting for Google or some such entity to come up with the research for mining methodology.

I’m going to presume you’re not conducting illegal activity such that you’re worried about getting caught. Given that presumption, what risks are you trying to mitigate by treating your cell phone as you describe?

Knowing what companies are on the market. My cell phone location would pretty much tell you who is being invested in or about to be sold. That could really cause trouble.

if a party was going to go to the trouble of getting access to your phone geo data, couldn’t they just as easily put a tail on you?

I don't think that would be a strategy that would work for very long, and besides that, why make it easy?

William Binney once said in an interview that one could also analyze which pair (or cluster) of cellphones went off together, and then analyze possible rendezvous.

I think one way to circumvent this is to force all participants to keep the cellphones in their offices/homes, and then meet elsewhere at a predetermined time, with no one carrying phones.

As many security professionals often say, it's not about whether I do any illegal activity, it is also about whether someone can "impersonate" me for various crimes like phishing. The less sensitive information people know about you, the safer it is for you.

I live in a country which retains phone location data for 2 years and can be warantlessly accessed by hundreds of government agencies down to tiny local councils and has zero oversight. Would love to "mitigate" the risks of that information falling into the wrong hands whether legally accessed or not, sadly it's too much effort so I don't.

Someone you know may be without your knowing and you can be snapped up in the "drag net"...

The "Red Sparrow" series was written by a former CIA operative. There are some good books by ex-CIA people. They get censored somewhat, but the general concepts come through.

The field people in HUMINT are called "case officers". Their job is to recruit and manage spies, not spy themselves. It's a strange combination of sales, human resources, and counseling. Dulles was from that world.

The big difference today is that the targets are smaller.

Back in the Cold War era, I worked for a company that built stuff for the three-letter agencies. They were all focused on the USSR; anything else was almost a spare time activity. It was a huge culture shock to the intelligence community when the USSR went down. First there was a big downsizing in intel. Then all the little players who had been squelched by the superpowers started asserting themselves, and the US intel community struggled to figure out what to do. The agencies had the wrong expertise and capabilities. And the wrong speed. The USSR was a very slow moving opponent. The little players moved much faster.

During the Cold War, huge efforts were put into finding out very general things about what the Soviet Union was doing - how many bombers, how many missiles, where the air bases were. Big attack surface. Today, it's trying to find some tiny terrorist group and getting someone to talk.

As others have said, it would probably be more difficult today to hide. Things like access to mass collected information from cameras (traffic, security, etc), cell phone location logs, face recognition, passport databases being leaked etc.

The OPM hack highlighted how opponents will attack weakest points such as the database of background check data. Now supposedly the Chinese know the detailed backgrounds, the secrets, even biometrics of millions of US agents.

The Russian passport database was leaked, which allow independent investigators to track down and prove that the Skripal assassins were GRU officers. It was based on special markings in the database and the sequential passport numbers:

https://www.bellingcat.com/news/uk-and-europe/2018/10/09/ful...

It was further confirmed by researches looking through tons of photos posted on the wall of Russian military academies to find Chepiga - one of the assassins:

https://www.bellingcat.com/news/uk-and-europe/2018/10/02/ana...

What's interesting here is that the exposure is not only to other state actors (who will presumably keep it secret) but also to these independent researchers, and leakers (Snowden), who don't mind laying it out for the whole world to see.

The resolution and zoom capabilities is absolutely astounding of those little traffic cameras we see.

They would surely remove the point about not leaving a public phone book open on a hot page.

Probably not. While that rule is becoming dated, it's general form: not leaving hot pages out and exposed, still makes great sense. And there's no reason to rescind the rules, unless they really do become invalidated. It would just be amendments to an already existing and robust practice.

And frankly, there still are places where a phone book is still in use.