I think people are afraid, very afraid.What are they protesting about ? Is it Trump or just life in general.
I guess american people are worried about their healthcare, global warming, women's rights, lgbt rights, racial discrimination, freedom of press, science budgets, anti-vax sentiments, and so much more
Heck i am worried, and i am not even American. I am worried because the largest military in the world (largest with such a great margin, it becomes ridiculous), is lead by an orange haired, mentally deficient, failed reality star.
I am worried that Trump's incompetence, aggravated by a combination of arrogance, ignorance, and narcissism, will cause a war on a large scale.
Whether this worry is justified or not, the fact that it exists, and keeping in mind that most Americans did not vote for Trump, explaines the protests.