I am usually not particularly interested in what Oliver Stone has to say, but this was of interest:

The Vietnam Memorial Wall in D.C. contains the names of 58,272 Americans who died in the war. Its message is that the tragedy of that wretched war was that 58,000 Americans died. The wall is 146 feet long. Imagine a wall that also contained the names of all the Vietnamese, Cambodians, Laotians, and others who died. Such a wall would be over 4 miles long.

For this curious that is 8.5 million. 

Most estimates I have seen are around 5 million. So that would be 2 1/3 miles. It would be quite a memorial.