Supporters typically supported the ideas of containment and domino theory.
Vietnam "hawks" or supporters of the war wanted to see Communism defeated. The war with Vietnam provided an opportunity to contain and possibly destroy Communism. They supported an "any means necessary" approach to defeat Vietnamese aggression which pulled us into war.
Fingerprint matching is determined through unique characteristics. To achieve it must have certain ridges. loops and whorls. The characteristic points are then compared to the prints on the system. When forensics finds that there are enough similar matching points, they state whether they are fingerprints in which they match or not.
It is assumed that prints are one hundred percent positive, that is their use is one hundred percent successful with a zero error.
However, the prints are not considered scientific evidence, but it is still a presumption. There is never a hundred percent matching the prints, but just the similarity within the prints.