Newby is a good reporter. The book reads like a long article from Time Magazine. The logic is measured and even-handed. Much of this was occurring during the height of the Cold War, until Nixon purportedly ended it in 1969. We wanted multiple contingencies. We eyed bioagents that could kill large swaths. We looked at bioagents that could kill just one or two, and do so discreetly.
We also studied bioagents that would not necessarily kill. If I understood correctly, the goal, in theory, would be to cause sweeping economic harm without anyone knowing we did anything; to make people sick in adversarial countries, and have their doctors not be able to figure out what was wrong. People grow sick, and once sick, stay sick. The burden on any nations economy if enough were disabled could be crippling. And one of the vectors they were most keen on was the tick.