Reddit reviews The Art of Intelligence: Lessons from a Life in the CIA's Clandestine Service

Some really great choices, but I'd also suggest https://www.amazon.com/Art-Intelligence-Lessons-Clandestine-Service/dp/0143123378

Henry was state Dept ambassador in charge of countering terrorism which is a big deal geopolitically

Well, there are two problems here, and both relate to the terms ninjutsu and taijutsu, and both are due to people inferring more than what is actually said.

Both are just general terms, and people misuse both. So, ninjutsu is just intelligence gathering techniques. I mean the CIA technically practices ninjutsu, but no one calls it ninjutsu. The English term used most is "Spycraft." During WWII, the Japanese taught indivduals ninjutsu. It was called the Nakano School.

Now, to be a good spy, one should know some hand to hand in case things go really bad. This is where taijutsu comes in. But taijutsu just means "body techniques." Technically, every martial art is this, and it's the equivalent of "fighting method." Nothing special. The Bujinkan has taken the 6 samurai arts that it teaches and called those "ninpo taijutsu" or "Bujinkan Budo taijutsu", which is just their form of arts, no different from saying something like Gracie Jujutsu. Most of the modern school stuff comes from Kukishinden ryu, which stems from a koryu, Kukishin Ryu. TEchnically, you could be a ninja and learn any fighting method you wanted.

The last thing is that none of the modern schools actually state that they teach ninjutsu. They say things like "ninpo taijutsu" or "the fighting art of the ninja." Scrub their websites and you will find that you won't find them saying that they teach ninjutsu. Even Stephen K. Hayes's most well know book, The Ninja and Their Secret Fighting Art, only talks about "ninjutsu" for 31 of its 156 pages, and even then, it's mostly from a historical perspective. The other books do so in a similar fashion.

In reality, there are better methods today than there were back then. Camouflage used to be a secret technique, but now there are books on it everywhere, and you can learn it from different sources.

It's either in "The Art of Intelligence", or "The Great War of Our Time where the author states that every country will place a spy in certain diplomatic positions. He mentions that the CIA places case officers in certain Secretary of State positions at certain embassies/consulates.

But that Russia is notorious and much more aggresive for doing such. So much so that if you are talking to a Russian diplomat or Ambassador you can almost be certain he/she is a spy.

Heck, if you watch the documentary Icarus about Russian doping, they mention agents from the FSB security service positioned at sites around Sochi to facilitate there doping program.

With no oversight whatsoever by any elected legislature or executive. There's so much misinformation about the IC it's not even funny. Go read http://www.amazon.com/The-Art-Intelligence-Lessons-Clandestine/dp/0143123378 or similar work. Or just any authoritative history.