Until about the last 20 minutes, ICE STATION ZEBRA is pretty much reference material. It looks and sounds fantatstic. It's certainly reference material for it's era. After the two hour mark (give or take...I don't recall the time stamps) there there's some odd wobble and zoom in a few instances and some really bad optical effects that are very soft and display some static damage on the image. Almost a home run...except for a couple of unforced errors late in the game.
In most ways, it's actually the most realistic of the cold war thrillers. Submarines did (and still do) engage in a lot of intelligence gathering and espionage work. Some are equipped specifically to deliver swimmers and landing parties. It's just slightly unfortunate that the sub in ICE STATION ZEBRA is a WWII Balao class diesel-electric with a 1950's "GUPPY" conversion. It's not remotely like the atomic sub it's claimed to be but I guess that's all the Navy had available for shooting.
I have too many problems with most of the other cold-war thrillers of the era (DR. STRANGELOVE, as a dark comedy, is excepted). The characters in THE BEDFORD INCIDENT strike me as caricatures of cliches . Just way over the top. FAIL SAFE, for all of it's talented, powerhouse cast, is completely absurd.