Social media was already massive, it was just primarily Facebook and Twitter (Arab Spring heavily involved social media). The US tea party movement had been around for a few years, some people were still very jazzed up about Affordable Care Act, only part of the defense of marriage act had been overturned and lawsuits would continue for a few more years. Conservatives hated Obama and were already talking about taking their country back.

Most everything in the US is just extrapolation plus some pandemic fuel.