No, I wouldn’t say that’s a good summary, and the phenomenon was unfortunately much too complex to be described with a one-liner with any degree of accuracy.

The fundamental problem with such simple summaries is that they implicitly assume an oversimplified historical background to the whole situation: the U.S. pitched against the U.S.S.R. in a state of all-out Cold War hostility, with the entire U.S. government acting in a coherent way as a unified entity in this struggle for global supremacy, and individuals accused of acting as Soviet agents being either conscious and willing traitors working for Moscow or innocent victims of a witch-hunt. One must replace these simplistic preconceptions with a much more nuanced and detailed view before one can even begin to form anything more than a cartoonish picture of the so-called "Second Red Scare" period. (Which was in fact well underway, with the HUAC hearings, the Hollywood blacklist, the Hiss-Chambers affair, etc., years before McCarthy came to any national prominence.)

I could write a great deal about this topic, but I think that such a lengthy off-topic diversion would probably be too much.