Final answer:
An exact count of anti-war protestors in the U.S by 1969 is not available, but the movement included hundreds of thousands or possibly millions of individuals. The Moratorium to End the War in Vietnam held in October 1969 saw up to half a million people protesting in Washington D.C.
Step-by-step explanation:
It's challenging to provide a specific count of anti-war protestors in the United States by 1969 due to the fact that records of such statistics were not rigorously maintained. However, it's known that by this time, the anti-war movement had developed into a mass movement with hundreds of thousands, possibly millions, of individuals involved across the country. The largest protest, the Moratorium to End the War in Vietnam which occurred in October of 1969, gathered an estimated half a million people in Washington, D.C. alone. Therefore, it's safe to say that the number was quite substantial, but a specific count is unclear.
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