We are not a trusting people. But, it wasn't always this way.
Check out this GIF created by Josh Morgan using data from the National Opinion Research Center's General Social Survey (GSS) from 1972 to 2012. Morgan collected the responses to this simple question on the GSS: "Generally speaking, would you say that most people can be trusted or that you can’t be too careful in dealing with people?"
Not a pretty picture.
As Morgan notes in a fascinating Medium piece on our declining trust in one another: "The percentage of all respondents who said that most people can be trusted dropped from about 46 percent in 1972 to about 32 percent in 2012."
Morgan doesn't attempt to draw a single conclusion for the "why" behind our erosion in trust. And, there's no way a single factor is responsible for such a large societal change. But, he does note that the ubiquity of television, the Internet and smart phones have fueled less direct human interaction and, therefore, perhaps also fueled a lack of willingness to give others the benefit of the doubt.