Political polarization in the United States has been steadily and rapidly increasing since the early 2000s and some scholars argue that the development of social networks may have been the cause (Sunstein, 2018). On the contrary, there is an emerging body of studies that contradict this belief and even state that social media use positively affects political knowledge (Nguyen & Vu, 2019).
The purpose of this thesis is to answer the question of whether Facebook use has an impact on political polarization in the United States and why this impact occurs. To achieve this, a systematic literature review was conducted based on the concept of Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) (Moher et al., 2009) Consequently, 34 studies on the effect of Facebook use on political polarization in the United States were identified and analyzed. As a result, 53% of the studies concluded that Facebook use decreases or does not affect political polarization in the United States, while 47% indicated that it increases it. The most common explanation for the increasing effect was the creation of an echo chamber on Facebook. On the other hand, the prevalent reason why Facebook led to political depolarization in the United States was the exposure of its users to counter-attitudinal views.
Due to the small numerical difference between the analysed studies with opposing results, it is difficult to say that Facebook use has a greater decreasing or no effect on political polarization in the United States. But contrary to the widespread belief that the use of social networks such as Facebook increases political polarization in the United States, slightly more than half of all the studies analysed in this paper concluded that Facebook use does not affect or even decreases political polarization in the United States.