I would go back to world war 2 and help the Americans British and French to stop the Germens. 1939 to 1945 was the year that WW2 started and ended and millions of inccent people died because of Adolf Hitler. In 1945 the Germens lost war unfornetly it last 7 years. So, that is why I would go back and try to make a differnce and help save more peoples lives
It means that even it everyone is doing something wrong, it is not right. It is referring to peer pressure, don't do something just because everyone else it doing it.
In this situation, Huck is trying to be impressive. He is trying to get the point across that he is funny and "cool". This lie is not only the one of a kind for Huck, but also one where he tries to push his reputation past its limits.