Answer:
the bystander effect
Explanation:
The bystander effect is the social psychological phenomenon that occurs when individuals are less likely to intervene to help someone in an emergency. The greater the number of observer present at the site of a situation, the less likely would be a probability of helping hand. In contrast to this people would react more likely when there no or few witnessed present. There are many reasons recorded-for this effect like ambiguity, diffusion of responsibility, cultural difference, etc.
The start of the war in Europe is generally held to be 1 September 1939<span>, beginning with the German invasion of Poland; Britain and France declared war on Germany two days later.</span>
A strategy by President Richard Nixon for ending U.S involvement in the Vietnam war.This involved a gradual withdrawal of south Vietnamese forces .This went along with the Nixon Doctrine