Answer:
It is being referred to as an insurrection because it was extremely violent.
Explanation:
A protest is peaceful most of the time. The definition for protest is, "A protest is a public expression of objection, disapproval or dissent towards an idea or action, typically a political one." As you can see, it does not mention it being violent in any way. Here is the definition for insurrection: "Rebellion, uprising, or insurrection is a refusal of obedience or order. It refers to the open resistance against the orders of an established authority." There is a pretty big difference.
