The Vietnam Morass

I happened to try to check Jill Lepore's claim that hundreds of thousands marched on April 15, 1967 in New York City to protest the war--it seemed high to me. That got me into deep waters.  The NY Times seems to say that police estimated 100,000, or possibly 125,000, although they were told to prepare for 200,000 to 400,000. Elsewhere including wikipedia the "hundreds of thousands" phrase seems to be established wisdom.  Not sure anyone has tried to estimate it as carefully as we used to do with crowds at the various inaugurals.

Elsewhere there's the question of the number of draft dodgers--Wikipedia offers different vague estimates in different places, but this site has:

For its part, the U.S. government continued to prosecute draft evaders after the Vietnam War ended. A total of 209,517 men were formally accused of violating draft laws, while government officials estimate another 360,000 were never formally accused.

That sounds so specific it must be based on some official document; unfortunately they don't provide any sources. 

It's a reminder to me of how fragile is the base of "facts" for our received version of history.