What the reason the US did not want to get in to world war 2?

The US had already been involved with one European embroilment during the 1st World War (originally called the Great War, prior to WW2); and didn't relish the idea of another one. Germany/Japan may have attacked other nations; but they weren't attacking the US. Of all of the MAIN combatants, the US was the most geographically isolated from aggression (the Americas-North America, Central America, South America...of which the latter two remained neutral through out the war).